A186892 Nonprime numbers n such that the Stern polynomial B(n,x) is irreducible.

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: A123825 A349416 A157269 * A206075 A276448 A176275

Adjacent sequences: A186889 A186890 A186891 * A186893 A186894 A186895

Keyword

nonn

Author

T. D. Noe, Feb 28 2011

Status

approved