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A244505 Greater of twin primes of (40n-23,40n-21). 1
19, 139, 619, 859, 1699, 2659, 3259, 4219, 4339, 5419, 5659, 7459, 8539, 9859, 10459, 10939, 11059, 11779, 12379, 13219, 13339, 15139, 15739, 17419, 17659, 19699, 20899, 21019, 21379, 21739, 22699, 23059, 23539, 24979, 25579, 27739, 28099, 30139, 32059 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
This is a subsequence and the intersection of A006512 (greater of twin primes) and A142190 (primes 19 mod 40).
LINKS
Chris K. Caldwell, Twin primes
Eric Weisstein's World of Mathematics, Twin Primes
MATHEMATICA
Select[40*Range[1000]-21, AllTrue[{#, #-2}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Oct 04 2019 *)
PROG
(Python) from sympy import isprime
for n in range(1, 2001):
..if isprime(40*n-23) and isprime(40*n-21): print(40*n-21, end=", ")
(PARI) lista(nn) = for(n=1, nn, if(isprime(q=40*n-21) && isprime(q-2), print1(n, ", "))); \\ Michel Marcus, Nov 12 2014
CROSSREFS
Sequence in context: A221226 A139902 A140624 * A235146 A057636 A104046
KEYWORD
nonn
AUTHOR
Karl V. Keller, Jr., Nov 11 2014
STATUS
approved

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Last modified March 19 06:32 EDT 2024. Contains 370953 sequences. (Running on oeis4.)