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Decades whose prime pattern is the same as prime pattern in the previous decade.
2

%I #10 Dec 08 2012 02:17:37

%S 38,79,114,125,134,135,140,155,168,181,219,235,249,277,289,292,311,

%T 315,324,332,348,375,419,431,437,445,477,485,500,513,525,533,537,546,

%U 559,561,576,597,610,617,625,641,649,651,675,693,697,707,709,714,718,727

%N Decades whose prime pattern is the same as prime pattern in the previous decade.

%H V. Raman, <a href="/A219999/b219999.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) >> n log^2 n.

%F a(n) = A216287(n) + 1.

%e The primes between 380 and 390 are 383 and 389. The primes in the previous decade are 373 and 379. Therefore 38 is in the sequence.

%t Select[Range[2, 100], Mod[Prime[Range[PrimePi[NextPrime[10#]], PrimePi[10# + 10]]], 10] == Mod[Prime[Range[PrimePi[NextPrime[10# - 10]], PrimePi[10#]]], 10] (* _Alonso del Arte_, Dec 07 2012 *)

%o (PARI) for(i=2,1000,if(isprime(10*i-9)==isprime(10*i+1)&&isprime(10*i-7)==isprime(10*i+3)&&isprime(10*i-3)==isprime(10*i+7)&&isprime(10*i-1)==isprime(10*i+9),print1(i", ")))

%Y Cf. A190639.

%Y Cf. A216287 (lower decade).

%K nonn,base

%O 1,1

%A _V. Raman_, Dec 07 2012