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A219999
Decades whose prime pattern is the same as prime pattern in the previous decade.
2
38, 79, 114, 125, 134, 135, 140, 155, 168, 181, 219, 235, 249, 277, 289, 292, 311, 315, 324, 332, 348, 375, 419, 431, 437, 445, 477, 485, 500, 513, 525, 533, 537, 546, 559, 561, 576, 597, 610, 617, 625, 641, 649, 651, 675, 693, 697, 707, 709, 714, 718, 727
OFFSET
1,1
FORMULA
a(n) >> n log^2 n.
a(n) = A216287(n) + 1.
EXAMPLE
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.
MATHEMATICA
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 *)
PROG
(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", ")))
CROSSREFS
Cf. A190639.
Cf. A216287 (lower decade).
Sequence in context: A044104 A044485 A160846 * A219997 A039421 A043244
KEYWORD
nonn,base
AUTHOR
V. Raman, Dec 07 2012
STATUS
approved