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A130490 a(n) = Sum_{k=0..n} (k mod 12) (Partial sums of A010881). 3
0, 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 66, 66, 67, 69, 72, 76, 81, 87, 94, 102, 111, 121, 132, 132, 133, 135, 138, 142, 147, 153, 160, 168, 177, 187, 198, 198, 199, 201, 204, 208, 213, 219, 226, 234, 243, 253, 264, 264, 265, 267, 270, 274, 279, 285, 292, 300 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Let A be the Hessenberg n by n matrix defined by: A[1,j] = j mod 12, A[i,i]:=1, A[i,i-1]=-1. Then, for n >= 1, a(n)=det(A). - Milan Janjic, Jan 24 2010

LINKS

Shawn A. Broyles, Table of n, a(n) for n = 0..1000

FORMULA

a(n) = 66*floor(n/12) + A010881(n)*(A010881(n) + 1)/2.

G.f.: g(x) = (Sum_{k=1..11} k*x^k)/((1-x^12)(1-x)).

Also, g(x) = x(11x^12-12x^11+1)/((1-x^12)(1-x)^3).

PROG

(PARI) a(n) = sum(k=0, n, k % 12); \\ Michel Marcus, Apr 29 2018

CROSSREFS

Cf. A010872, A010873, A010874, A010875, A010876, A010877, A010878, A010879, A010880, A130481, A130482, A130483, A130484, A130485, A130486, A130487, A130488, A130489.

Sequence in context: A261422 A262544 A033443 * A033444 A061791 A268291

Adjacent sequences:  A130487 A130488 A130489 * A130491 A130492 A130493

KEYWORD

nonn

AUTHOR

Hieronymus Fischer, May 31 2007

STATUS

approved

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Last modified August 19 17:41 EDT 2018. Contains 313880 sequences. (Running on oeis4.)