A216287 Decades whose prime pattern repeat in the next decade.

37, 78, 113, 124, 133, 134, 139, 154, 167, 180, 218, 234, 248, 276, 288, 291, 310, 314, 323, 331, 347, 374, 418, 430, 436, 444, 476, 484, 499, 512, 524, 532, 536, 545, 558, 560, 575, 596, 609, 616, 624, 640, 648, 650, 674, 692, 696, 706, 708, 713, 717, 726

Offset: 1

Author

V. Raman, Sep 03 2012

Keywords

• nonn
• base

Links

• T. D. Noe, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A190639.

Cf. A219999 (upper decade).

Programs

Mathematica

ps0 = {2, 3, 5, 7}; t = {}; Do[ps1 = Select[Range[10 n, 10 n + 9], PrimeQ]; If[Length[ps0] == Length[ps1] && ps0 + 10 == ps1, AppendTo[t, n - 1]];  ps0 = ps1, {n, 2, 1000}]; t (* T. D. Noe, Sep 03 2012 *)

PARI

isok(i)=isprime(10*i+1)==isprime(10*i+11) && isprime(10*i+3)==isprime(10*i+13) && isprime(10*i+7)==isprime(10*i+17) && isprime(10*i+9)==isprime(10*i+19) \\ V. Raman, Dec 08 2012

Formula

a(n) >> n log^2 n. - Charles R Greathouse IV, Sep 07 2012

a(n) = A219999(n) - 1. - V. Raman, Dec 08 2012