A084096 Fifth row of number array A084061.

1, 1, 8, 63, 656, 8525, 133120, 2430547, 50839808, 1199150649, 31495553024, 911770726823, 28846956187648, 990358890251653, 36670756251238400, 1456804472261953275, 61808742217201811456, 2789456491560247772657

Offset: 0

Author

Paul Barry, May 11 2003

Keywords

• easy
• nonn

Links

• G. C. Greubel, Table of n, a(n) for n = 0..300

Crossrefs

Cf. A084061, A084062, A084063, A084064, A084065, A084095.

Programs

GAP

List([0..20], n-> ((n-2)^n + (n+2)^n)/2); # G. C. Greubel, Jan 11 2020

Magma

[((n-2)^n + (n+2)^n)/2: n in [0..20]]; // G. C. Greubel, Jan 11 2020

Maple

seq( ((n-2)^n + (n+2)^n)/2, n=0..20); # G. C. Greubel, Jan 11 2020

Mathematica

Table[((n+2)^n + (n-2)^n)/2, {n,0,20}] (* G. C. Greubel, Jan 11 2020 *)

PARI

vector(21, n, ((n-3)^(n-1) + (n+1)^(n-1))/2 ) \\ G. C. Greubel, Jan 11 2020

Sage

[((n-2)^n + (n+2)^n)/2 for n in (0..20)] # G. C. Greubel, Jan 11 2020

Formula

a(n) = ((n - sqrt(4))^n + (n + sqrt(4))^n)/2 = ((n+2)^n + (n-2)^n)/2.