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A186892
Nonprime numbers n such that the Stern polynomial B(n,x) is irreducible.
3
1, 25, 55, 65, 77, 91, 95, 115, 121, 125, 133, 143, 145, 161, 169, 175, 185, 203, 205, 209, 215, 235, 245, 247, 253, 265, 289, 295, 299, 301, 305, 319, 323, 329, 335, 343, 361, 377, 391, 395, 407, 415, 425, 427, 445, 451, 469, 473, 475, 485, 493, 505, 515, 517, 529, 533, 539, 545, 551, 559, 575, 581, 583, 623, 625
OFFSET
1,2
COMMENTS
See A186891 for all numbers n such that the Stern polynomial B(n,x) is irreducible.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
PROG
(PARI) ps(n)=if(n<2, n, if(n%2, ps(n\2)+ps(n\2+1), 'x*ps(n\2)))
is(n)=!isprime(n) && polisirreducible(ps(n)) \\ Charles R Greathouse IV, Apr 07 2015
CROSSREFS
Sequence in context: A349416 A157269 A371129 * A206075 A276448 A176275
KEYWORD
nonn
AUTHOR
T. D. Noe, Feb 28 2011
STATUS
approved