A160413 a(n) = A160411(n+1)/4.

2, 1, 7, 2, 13, 3, 19, 4, 25, 5, 31, 6, 37, 7, 43, 8, 49, 9, 55, 10, 61, 11, 67, 12, 73, 13, 79, 14, 85, 15, 91, 16, 97, 17, 103, 18, 109, 19, 115, 20, 121, 21, 127, 22, 133, 23, 139, 24, 145, 25, 151, 26, 157, 27, 163, 28, 169, 29, 175, 30, 181, 31, 187, 32, 193

Offset: 1

Author

Omar E. Pol, Jun 13 2009

Keywords

• nonn
• easy

Links

• Index entries for linear recurrences with constant coefficients, signature (0,2,0,-1).

Crossrefs

Cf. A152978, A160117 A160411, A160417.

Programs

Mathematica

LinearRecurrence[{0, 2, 0, -1}, {2, 1, 7, 2, 13}, 100] (* Amiram Eldar, Feb 02 2024 *)

Formula

G.f.: x*(x^4 + 3*x^2 + x+2) / ((x-1)^2*(x+1)^2). - Colin Barker, Mar 04 2013

From Colin Barker, Apr 06 2013: (Start)

a(n) = -1 + (-1)^n - (1/4)*(-7 + 5*(-1)^n)*n for n > 1.

a(n) = 2*a(n-2) - a(n-4) for n > 5. (End)

Extensions

More terms from Colin Barker, Apr 06 2013

More terms from Amiram Eldar, Feb 02 2024