A066107 a(0) = 0; for n > 0, a(2n+1) = (2n+1)*(2n+3); a(2n) = 2n + 2.

0, 3, 6, 15, 10, 35, 14, 63, 18, 99, 22, 143, 26, 195, 30, 255, 34, 323, 38, 399, 42, 483, 46, 575, 50, 675, 54, 783, 58, 899, 62, 1023, 66, 1155, 70, 1295, 74, 1443, 78, 1599, 82, 1763, 86, 1935, 90, 2115, 94, 2303, 98, 2499, 102, 2703, 106, 2915, 110, 3135

Offset

0,2

Links

Harry J. Smith, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (0,3,0,-3,0,1).

Formula

O.g.f.: (3x+6x^2+6x^3-8x^4-x^5+2x^6)/(1-x^2)^3. - Len Smiley, Dec 06 2001

Mathematica

LinearRecurrence[{0, 3, 0, -3, 0, 1}, {0, 3, 6, 15, 10, 35, 14}, 60] (* Harvey P. Dale, Mar 14 2018 *)

Prog

(PARI) a(n) = polcoeff((3*x+6*x^2+6*x^3-8*x^4-x^5+2*x^6)/(1-x^2)^3+x*O(x^n), n) for(n=0, 100, print1(a(n), ", "))
(PARI) { for (n=0, 1000, if(n==0, a=0, if(n%2, a=n*(n + 2), a=2*n+2)); write("b066107.txt", n, " ", a) ) } \\ Harry J. Smith, Nov 15 2009

Crossrefs

Sequence in context: A144654 A132279 A334042 * A162276 A261955 A144615

Adjacent sequences: A066104 A066105 A066106 * A066108 A066109 A066110

Keyword

easy,nonn

Author

George E. Antoniou, Dec 05 2001

Status

approved