Prime p₀= 1271947839457482221 starts a Symmetric tuple of 18 consecutive primes (SPT).
d_n: 0 20 40 42 38 6 6 30 34 20 34 30 6 6 38 42 40 20 (?)
a_n: 0 20 60 102 140 146 152 182 216 236 270 300 306 312 350 392 432 452
All 18 integers p_n = p₀+a_n = p_n-1+d_n are prime and there are no other primes in the gaps.
diameter: 452
Found by: stoneageman
db: batch=77, k=18, 20 40 42 38 6 6 30 34 20

TPT(16)	1271946082524403721	0 2 66 68 138 140 156 158 210 212 240 242 246 248 348 350	-1756933078500
STPT(10)	1271946100993155569	0 2 18 20 60 62 102 104 120 122	-1738464326652
SPT(16)	1271946456682159669	0 28 34 64 82 88 112 132 160 180 204 210 228 258 264 292	-1382775322552
SPT(16)	1271946559212752783	0 8 20 38 50 150 210 218 246 254 314 414 426 444 456 464	-1280244729438
SPT(16)	1271946567534510409	0 10 24 34 40 70 112 120 124 132 174 204 210 220 234 244	-1271922971812
STPT(10)	1271947562266226117	0 2 30 32 42 44 54 56 84 86	-277191256104
SPT(16)	1271947949581060211	0 20 50 56 66 96 126 168 188 230 260 290 300 306 336 356	110123577990
SPT(16)	1271948306295189379	0 10 24 52 82 120 150 162 250 262 292 330 360 388 402 412	466837707158
STPT(10)	1271948527356837191	0 2 36 38 78 80 120 122 156 158	687899354970
STPT(10)	1271948697408341177	0 2 30 32 42 44 54 56 84 86	857950858956
STPT(10)	1271948882710478351	0 2 36 38 78 80 120 122 156 158	1043252996130