A017239 a(n) = (9*n + 6)^7.

279936, 170859375, 4586471424, 42618442977, 230539333248, 897410677851, 2799360000000, 7446353252589, 17565568854912, 37725479487783, 75144747810816, 140710042265625, 250226879128704, 425927596977747

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..10000
• Index entries for linear recurrences with constant coefficients, signature (8, -28, 56, -70, 56, -28, 8, -1).

Crossrefs

Cf. A001015 (n^7), A017233 (9*n+6).

Programs

Magma

[(9*n+6)^7: n in [0..25]]; // Vincenzo Librandi, Jul 25 2011

Mathematica

(9*Range[0,20]+6)^7 (* or *) LinearRecurrence[{8,-28,56,-70,56,-28,8,-1},{279936,170859375,4586471424,42618442977,230539333248,897410677851,2799360000000,7446353252589},20] (* Harvey P. Dale, Feb 11 2015 *)

Formula

a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8); a(0)=279936, a(1)=170859375, a(2)=4586471424, a(3)=42618442977, a(4)=230539333248, a(5)=897410677851, a(6)=2799360000000, a(7)=7446353252589. - Harvey P. Dale, Feb 11 2015