Take 1x number from the grid with 6x6 the same 3x3 magic square and add 9x [number -/- 1] of the same cell from the second grid with the '3x3 blown up' 6x6 magic square.
1x number
2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 |
7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 |
6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 |
2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 |
7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 |
6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 |
2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 |
7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 |
6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 |
2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 |
7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 |
6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 |
2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 |
7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 |
6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 |
2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 | 2 | 9 | 4 |
7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 | 7 | 5 | 3 |
6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 | 6 | 1 | 8 |
+ 9 x (number -/- 1)
20 | 20 | 20 | 29 | 29 | 29 | 9 | 9 | 9 | 27 | 27 | 27 | 4 | 4 | 4 | 22 | 22 | 22 |
20 | 20 | 20 | 29 | 29 | 29 | 9 | 9 | 9 | 27 | 27 | 27 | 4 | 4 | 4 | 22 | 22 | 22 |
20 | 20 | 20 | 29 | 29 | 29 | 9 | 9 | 9 | 27 | 27 | 27 | 4 | 4 | 4 | 22 | 22 | 22 |
11 | 11 | 11 | 2 | 2 | 2 | 36 | 36 | 36 | 18 | 18 | 18 | 31 | 31 | 31 | 13 | 13 | 13 |
11 | 11 | 11 | 2 | 2 | 2 | 36 | 36 | 36 | 18 | 18 | 18 | 31 | 31 | 31 | 13 | 13 | 13 |
11 | 11 | 11 | 2 | 2 | 2 | 36 | 36 | 36 | 18 | 18 | 18 | 31 | 31 | 31 | 13 | 13 | 13 |
34 | 34 | 34 | 16 | 16 | 16 | 14 | 14 | 14 | 23 | 23 | 23 | 21 | 21 | 21 | 3 | 3 | 3 |
34 | 34 | 34 | 16 | 16 | 16 | 14 | 14 | 14 | 23 | 23 | 23 | 21 | 21 | 21 | 3 | 3 | 3 |
34 | 34 | 34 | 16 | 16 | 16 | 14 | 14 | 14 | 23 | 23 | 23 | 21 | 21 | 21 | 3 | 3 | 3 |
7 | 7 | 7 | 25 | 25 | 25 | 5 | 5 | 5 | 32 | 32 | 32 | 30 | 30 | 30 | 12 | 12 | 12 |
7 | 7 | 7 | 25 | 25 | 25 | 5 | 5 | 5 | 32 | 32 | 32 | 30 | 30 | 30 | 12 | 12 | 12 |
7 | 7 | 7 | 25 | 25 | 25 | 5 | 5 | 5 | 32 | 32 | 32 | 30 | 30 | 30 | 12 | 12 | 12 |
33 | 33 | 33 | 24 | 24 | 24 | 19 | 19 | 19 | 1 | 1 | 1 | 8 | 8 | 8 | 26 | 26 | 26 |
33 | 33 | 33 | 24 | 24 | 24 | 19 | 19 | 19 | 1 | 1 | 1 | 8 | 8 | 8 | 26 | 26 | 26 |
33 | 33 | 33 | 24 | 24 | 24 | 19 | 19 | 19 | 1 | 1 | 1 | 8 | 8 | 8 | 26 | 26 | 26 |
6 | 6 | 6 | 15 | 15 | 15 | 28 | 28 | 28 | 10 | 10 | 10 | 17 | 17 | 17 | 35 | 35 | 35 |
6 | 6 | 6 | 15 | 15 | 15 | 28 | 28 | 28 | 10 | 10 | 10 | 17 | 17 | 17 | 35 | 35 | 35 |
6 | 6 | 6 | 15 | 15 | 15 | 28 | 28 | 28 | 10 | 10 | 10 | 17 | 17 | 17 | 35 | 35 | 35 |
= (simple) 18x18 magic square
173 | 180 | 175 | 254 | 261 | 256 | 74 | 81 | 76 | 236 | 243 | 238 | 29 | 36 | 31 | 191 | 198 | 193 |
178 | 176 | 174 | 259 | 257 | 255 | 79 | 77 | 75 | 241 | 239 | 237 | 34 | 32 | 30 | 196 | 194 | 192 |
177 | 172 | 179 | 258 | 253 | 260 | 78 | 73 | 80 | 240 | 235 | 242 | 33 | 28 | 35 | 195 | 190 | 197 |
92 | 99 | 94 | 11 | 18 | 13 | 317 | 324 | 319 | 155 | 162 | 157 | 272 | 279 | 274 | 110 | 117 | 112 |
97 | 95 | 93 | 16 | 14 | 12 | 322 | 320 | 318 | 160 | 158 | 156 | 277 | 275 | 273 | 115 | 113 | 111 |
96 | 91 | 98 | 15 | 10 | 17 | 321 | 316 | 323 | 159 | 154 | 161 | 276 | 271 | 278 | 114 | 109 | 116 |
299 | 306 | 301 | 137 | 144 | 139 | 119 | 126 | 121 | 200 | 207 | 202 | 182 | 189 | 184 | 20 | 27 | 22 |
304 | 302 | 300 | 142 | 140 | 138 | 124 | 122 | 120 | 205 | 203 | 201 | 187 | 185 | 183 | 25 | 23 | 21 |
303 | 298 | 305 | 141 | 136 | 143 | 123 | 118 | 125 | 204 | 199 | 206 | 186 | 181 | 188 | 24 | 19 | 26 |
56 | 63 | 58 | 218 | 225 | 220 | 38 | 45 | 40 | 281 | 288 | 283 | 263 | 270 | 265 | 101 | 108 | 103 |
61 | 59 | 57 | 223 | 221 | 219 | 43 | 41 | 39 | 286 | 284 | 282 | 268 | 266 | 264 | 106 | 104 | 102 |
60 | 55 | 62 | 222 | 217 | 224 | 42 | 37 | 44 | 285 | 280 | 287 | 267 | 262 | 269 | 105 | 100 | 107 |
290 | 297 | 292 | 209 | 216 | 211 | 164 | 171 | 166 | 2 | 9 | 4 | 65 | 72 | 67 | 227 | 234 | 229 |
295 | 293 | 291 | 214 | 212 | 210 | 169 | 167 | 165 | 7 | 5 | 3 | 70 | 68 | 66 | 232 | 230 | 228 |
294 | 289 | 296 | 213 | 208 | 215 | 168 | 163 | 170 | 6 | 1 | 8 | 69 | 64 | 71 | 231 | 226 | 233 |
47 | 54 | 49 | 128 | 135 | 130 | 245 | 252 | 247 | 83 | 90 | 85 | 146 | 153 | 148 | 308 | 315 | 310 |
52 | 50 | 48 | 133 | 131 | 129 | 250 | 248 | 246 | 88 | 86 | 84 | 151 | 149 | 147 | 313 | 311 | 309 |
51 | 46 | 53 | 132 | 127 | 134 | 249 | 244 | 251 | 87 | 82 | 89 | 150 | 145 | 152 | 312 | 307 | 314 |
I have used method composite, simple to construct
9x9, 12x12, 15x15a, 15x15b, 18x18, 20x20, 21x21a, 21x21b, 24x24a, 24x24b, 25x25, 27x27a, 27x27b, 28x28, 30x30a, 30x30b