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A130490 Sum {0<=k<=n, k mod 12} (Partial sums of A010881). 2
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). [From Milan Janjic, Jan 24 2010]

LINKS

Table of n, a(n) for n=0..56.

FORMULA

a(n)=66*floor(n/12)+A010881(n)*(A010881(n)+1)/2. G.f.: g(x)=(sum{1<=k<12, k*x^k})/((1-x^12)(1-x)). Also: g(x)=x(11x^12-12x^11+1)/((1-x^12)(1-x)^3).

MAPLE

a:=n->add(chrem( [n, j], [1, 12] ), j=1..n):seq(a(n), n=0..56); # [From Zerinvary Lajos, Apr 07 2009]

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 February 17 20:22 EST 2018. Contains 299296 sequences. (Running on oeis4.)