OFFSET
0,2
COMMENTS
Partial sums of A056003.
If n is of the form 8*k+2*(-1)^k-1 or 8*k+2*(-1)^k-2 then a(n) is odd.
LINKS
Bruno Berselli, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (11,-55,165,-330,462,-462,330,-165,55,-11,1).
FORMULA
MAPLE
seq((9*n+10)*binomial(n+9, 9)/10, n=0..30); # G. C. Greubel, Aug 28 2019
MATHEMATICA
Table[(9n+10)Binomial[n+9, 9]/10, {n, 0, 30}]
PROG
(PARI) vector(30, n, n--; (9*n+10)*binomial(n+9, 9)/10)
(Sage) [(9*n+10)*binomial(n+9, 9)/10 for n in (0..30)]
(Magma) [(9*n+10)*Binomial(n+9, 9)/10: n in [0..30]];
(GAP) List([0..30], n-> (9*n+10)*Binomial(n+9, 9)/10); # G. C. Greubel, Aug 28 2019
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Bruno Berselli, Jan 26 2015
STATUS
approved