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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
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
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
KEYWORD
nonn
AUTHOR
Alois P. Heinz, May 16 2014
STATUS
approved