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A271981 Primes p such that p + 40 is also prime. 3
3, 7, 13, 19, 31, 43, 61, 67, 73, 97, 109, 127, 139, 151, 157, 193, 199, 211, 223, 229, 241, 271, 277, 307, 313, 349, 379, 409, 421, 439, 463, 523, 547, 577, 601, 607, 613, 619, 643, 661, 733, 757, 769, 787, 823, 907, 937, 991, 1009, 1021, 1051 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A126721 is a subsequence of this sequence.

LINKS

Karl V. Keller, Jr., Table of n, a(n) for n = 1..10000

EXAMPLE

3 is a term since 3 + 40 = 43 is also prime.

7 is a term since 7 + 40 = 47 is also prime.

MATHEMATICA

Select[Prime@ Range@ 180, PrimeQ[# + 40] &] (* Michael De Vlieger, Apr 18 2016 *)

PROG

(Python)

from sympy import isprime

for i in range(3, 2001, 2):

..if isprime(i) and isprime(i+40): print (i, end=', ')

(PARI) lista(nn) = forprime(p=2, nn, if (isprime(p+40), print1(p, ", "))); \\ Michel Marcus, Apr 19 2016

CROSSREFS

Cf. A000040, A126721.

Sequence in context: A167473 A256864 A231432 * A103521 A103966 A023237

Adjacent sequences:  A271978 A271979 A271980 * A271982 A271983 A271984

KEYWORD

nonn

AUTHOR

Karl V. Keller, Jr., Apr 17 2016

STATUS

approved

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Last modified October 21 17:37 EDT 2021. Contains 348155 sequences. (Running on oeis4.)