A216287 - OEIS

%I #21 Jan 01 2025 14:40:23

%S 37,78,113,124,133,134,139,154,167,180,218,234,248,276,288,291,310,

%T 314,323,331,347,374,418,430,436,444,476,484,499,512,524,532,536,545,

%U 558,560,575,596,609,616,624,640,648,650,674,692,696,706,708,713,717,726

%N Decades whose prime pattern repeat in the next decade.

%H T. D. Noe, <a href="/A216287/b216287.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) >> n log^2 n. - _Charles R Greathouse IV_, Sep 07 2012

%F a(n) = A219999(n) - 1. - _V. Raman_, Dec 08 2012

%t 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 *)

%o (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

%Y Cf. A190639.

%Y Cf. A219999 (upper decade).

%K nonn,base

%O 1,1

%A _V. Raman_, Sep 03 2012