A025773 - OEIS

A025773

Expansion of 1/((1-x)(1-x^4)(1-x^7)).

1, 1, 1, 1, 2, 2, 2, 3, 4, 4, 4, 5, 6, 6, 7, 8, 9, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 24, 26, 27, 28, 30, 32, 33, 34, 36, 38, 39, 41, 43, 45, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 69, 71, 73, 75

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OFFSET

0,5

COMMENTS

Partitions into parts 1, 4, and 7. - Joerg Arndt, May 01 2014

LINKS

Table of n, a(n) for n=0..59.

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

FORMULA

a(n) = floor((n^2+12*n+50+14*cos(n*Pi/2))/56). - Tani Akinari, May 01 2014

a(n)= +a(n-1) +a(n-4) -a(n-5) +a(n-7) -a(n-8) -a(n-11) +a(n-12). - R. J. Mathar, Aug 21 2014

CROSSREFS

Sequence in context: A004524 A265409 A126257 * A308303 A285763 A294621

Adjacent sequences: A025770 A025771 A025772 * A025774 A025775 A025776

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved