A249951 Numbers n such that A113630(n) is prime.

3, 5, 8, 23, 42, 62, 63, 75, 90, 98, 177, 192, 207, 213, 222, 228, 233, 263, 288, 297, 317, 320, 402, 453, 455, 528, 570, 602, 620, 650, 672, 752, 780, 797, 810, 863, 867, 870, 875, 912, 932, 935, 978, 1010, 1043, 1065, 1067, 1070, 1110, 1125, 1133, 1142, 1190

Offset

1,1

Comments

A113630(n) = 1 + 2*n + 3*n^2 + 4*n^3 + 5*n^4 + 6*n^5 + 7*n^6 + 8*n^7 + 9*n^8.

Links

Chai Wah Wu, Table of n, a(n) for n = 1..2434

Example

See example section of A113630.

Prog

(Python)
from sympy import isprime
A249951_list, m = [], [362880, -1229760, 1607760, -1011480, 309816, -40752, 1584, -4, 1]
for n in range(1, 10**5+1):
....for i in range(8):
........m[i+1]+= m[i]
....if isprime(m[-1]):
........A249951_list.append(n)
(PARI) for(n=1, 5000, s=sum(i=1, 9, i*n^(i-1)); if(ispseudoprime(s), print1(n, ", "))) \\ Derek Orr, Nov 09 2014
(Magma) [n: n in [0..1500] | IsPrime(1+2*n+3*n^2+4*n^3+ 5*n^4+6*n^5+7*n^6+8*n^7+9*n^8)]; // Vincenzo Librandi, Nov 09 2014
(Haskell)
a249951 n = a249951_list !! (n-1)
a249951_list = filter ((== 1) . a010051'' . a113630) [1..]
-- Reinhard Zumkeller, Nov 22 2014

Crossrefs

Cf. A113630.

Cf. A010051.

Sequence in context: A101984 A292492 A108460 * A368740 A373967 A353605

Adjacent sequences: A249948 A249949 A249950 * A249952 A249953 A249954

Keyword

nonn

Author

Chai Wah Wu, Nov 09 2014

Status

approved