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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

All terms are odd. - Jon Perry, Sep 11 2014

LINKS

Nathaniel Johnston, Table of n, a(n) for n = 1..10000

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

Adjacent sequences:  A246663 A246664 A246665 * A246667 A246668 A246669

KEYWORD

nonn

AUTHOR

Carmine Suriano, Sep 01 2014

STATUS

approved

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Last modified October 20 20:18 EDT 2019. Contains 328273 sequences. (Running on oeis4.)