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A246666
Numbers n such that n^3 + (n+1)^3 + (n+3)^3 is prime.
1
1, 3, 5, 9, 31, 43, 45, 51, 71, 89, 135, 141, 145, 149, 159, 163, 169, 183, 185, 225, 233, 241, 255, 261, 271, 281, 283, 285, 299, 309, 311, 313, 355, 395, 401, 411, 415, 423, 429, 435, 449, 453, 485, 491, 541, 551, 561, 579, 583, 589, 603, 621, 625, 635, 681
OFFSET
1,2
COMMENTS
All terms are odd. - Jon Perry, Sep 11 2014
LINKS
EXAMPLE
a(5)=31 since 31^3+(31+1)^3+(31+3)^3=101863 is prime.
MAPLE
isA246666 := proc (n) return isprime(n^3+(n+1)^3+(n+3)^3) end proc; seq(`if`(isA246666(2*n-1), 2*n-1, NULL), n = 1 .. 400); # Nathaniel Johnston, Sep 09 2014
PROG
(PARI) for(n=0, 10^3, if(isprime(n^3+(n+1)^3+(n+3)^3), print1(n, ", "))); \\ Joerg Arndt, Sep 09 2014
(Python)
from sympy import isprime
A246666_list = [n for n in range(1, 10**5) if isprime(3*n*(n*(n+4)+10)+28)]
# Chai Wah Wu, Sep 09 2014
CROSSREFS
Sequence in context: A209286 A082711 A013622 * A027715 A082703 A125708
KEYWORD
nonn
AUTHOR
Carmine Suriano, Sep 01 2014
STATUS
approved