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A036091

Centered cube numbers: (n+1)^13+n^13.

1, 8193, 1602515, 68703187, 1287811989, 14281397141, 109949704423, 646644824295, 3091621642217, 12541865828329, 44522712143931, 141515917523003, 409868311971325, 1096589879846397, 2739909841613519

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OFFSET

0,2

COMMENTS

Never prime, as a(n) = (2n + 1) * (n^12 + 6n^11 + 36n^10 + 125n^9 + 295n^8 + 496n^7 + 610n^6 + 553n^5 + 367n^4 + 174n^3 + 56n^2 + 11n + 1). Semiprime for n in {1, 8, 15, 21, 86, 135, 141, 249, 260, 278, 323, 326, 363, ...}. - Jonathan Vos Post, Aug 26 2011

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..10000

B. K. Teo and N. J. A. Sloane, Magic numbers in polygonal and polyhedral clusters, Inorgan. Chem. 24 (1985), 4545-4558.

MAPLE

A036091:=n->(n + 1)^13 + n^13; seq(A036091(n), n=0..20); # Wesley Ivan Hurt, Apr 01 2014

MATHEMATICA

Table[(n + 1)^13 + n^13, {n, 0, 20}] (* Wesley Ivan Hurt, Apr 01 2014 *)

PROG

(Magma) [(n+1)^13+n^13: n in [0..20]]; // Vincenzo Librandi, Aug 27 2011

CROSSREFS

Cf. A036085, A036087, A036088, A036089, A036090.

Sequence in context: A230190 A017689 A013961 * A181134 A345635 A346348

Adjacent sequences: A036088 A036089 A036090 * A036092 A036093 A036094

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane

STATUS

approved