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A242505 Number of compositions of n, where the difference between the number of odd parts and the number of even parts is 7. 2
1, 0, 7, 9, 28, 81, 139, 405, 815, 1771, 4092, 8173, 18019, 37609, 77246, 163345, 331968, 683631, 1400777, 2832362, 5770056, 11640546, 23446366, 47227530, 94582628, 189487950, 378658714, 754877809, 1504215522, 2990469337, 5939101301, 11782590061, 23340439078 (list; graph; refs; listen; history; text; internal format)
OFFSET

7,3

COMMENTS

With offset 14 number of compositions of n, where the difference between the number of odd parts and the number of even parts is -7.

LINKS

Alois P. Heinz, Table of n, a(n) for n = 7..1000

FORMULA

Recurrence (for n>=11): (n-7)*n*(n+1)*(n+14)*(16*n^4 + 64*n^3 + 56*n^2 - 16*n - 38431)*a(n) = -1568*(n-8)*n*(n+2)*(n+13)*(2*n+1)*a(n-1) + 2*(n+1)*(16*n^7 + 160*n^6 + 1192*n^5 + 472*n^4 - 49083*n^3 - 168912*n^2 - 1534048*n - 1379196)*a(n-2) + 2*n*(n+2)*(2*n+1)*(16*n^5 + 128*n^4 + 336*n^3 + 1076*n^2 - 36101*n - 8729)*a(n-3) - (n-4)*(n+1)*(n+2)*(n+3)*(16*n^4 + 128*n^3 + 344*n^2 + 352*n - 38311)*a(n-4). - Vaclav Kotesovec, May 20 2014

CROSSREFS

Column k=7 of A242498.

Sequence in context: A113124 A324986 A030404 * A263826 A066930 A247192

Adjacent sequences:  A242502 A242503 A242504 * A242506 A242507 A242508

KEYWORD

nonn

AUTHOR

Alois P. Heinz, May 16 2014

STATUS

approved

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Last modified August 9 21:08 EDT 2022. Contains 356026 sequences. (Running on oeis4.)