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A213436
Principal diagonal of the convolution array A212891.
2
1, 17, 84, 260, 625, 1281, 2352, 3984, 6345, 9625, 14036, 19812, 27209, 36505, 48000, 62016, 78897, 99009, 122740, 150500, 182721, 219857, 262384, 310800, 365625, 427401, 496692, 574084, 660185, 755625, 861056, 977152, 1104609
OFFSET
1,2
FORMULA
a(n) = (11*n^4 + 6*n^3 - 5*n^2)/12.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5).
G.f.: x*(1 + 12*x + 9*x^2)/(1 - x)^5.
MATHEMATICA
(See A212891.)
CROSSREFS
Sequence in context: A193046 A158528 A197346 * A239667 A344523 A156968
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jun 16 2012
STATUS
approved