A083200 Polynexus numbers of order 7.

0, 1, 17, 118, 514, 1681, 4529, 10612, 22380, 43473, 79057, 136202, 224302, 355537, 545377, 813128, 1182520, 1682337, 2347089, 3217726, 4342394, 5777233, 7587217, 9847036, 12642020, 16069105, 20237841, 25271442, 31307878, 38501009, 47021761

Offset

1,3

Links

Bruno Berselli, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (7,-21,35,-35,21,-7,1).

Formula

a(n) = ((n^7-(n-1)^7)-(n^3-(n-1)^3))/120.

G.f.: x^2*(1+10*x+20*x^2+10*x^3+x^4)/(1-x)^7. - Bruno Berselli, Feb 13 2012

Mathematica

Table[((n^7 - (n - 1)^7) - (n^3 - (n - 1)^3))/120, {n, 31}] (* Bruno Berselli, Feb 13 2012 *)

Crossrefs

Cf. A079547, A088889-A088894 (similar sequences).

Sequence in context: A196575 A003109 A066607 * A102353 A289663 A048714

Adjacent sequences: A083197 A083198 A083199 * A083201 A083202 A083203

Keyword

nonn,easy

Author

Xavier Acloque, Jun 01 2003

Extensions

More terms from David Wasserman, Oct 26 2004

Offset changed (according to the formula) from Bruno Berselli, Feb 13 2012

Status

approved