A141496 a(0)=1; a(1)=5; a(2)=11; a(n)=a(1)*a(n-1).

1, 5, 11, 55, 275, 1375, 6875, 34375, 171875, 859375, 4296875, 21484375, 107421875, 537109375, 2685546875, 13427734375, 67138671875, 335693359375, 1678466796875, 8392333984375, 41961669921875, 209808349609375

Offset: 0

Author

Roger L. Bagula, Aug 10 2008

Keywords

• nonn
• easy

Links

• Index entries for linear recurrences with constant coefficients, signature (5).

Crossrefs

Cf. A084215, A141495.

Programs

Mathematica

Clear[a] a[0] = 1; a[1] = 5; a[2] = 11; a[n_] := a[n] = a[1]*a[n - 1]; Table[a[n], {n, 0, 30}]

Formula

a(n) = 11*5^(n-2) for n>1. a(n) = 5*a(n-1) for n>2. G.f.: (1-14*x^2)/(1-5*x). [Colin Barker, Oct 13 2012]

Extensions

Edited by N. J. A. Sloane, Aug 16 2008