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A123615
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Column 5 of triangle A123610.
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4
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1, 6, 63, 392, 1764, 6352, 19404, 52272, 127413, 286286, 601203, 1192464, 2252432, 4078368, 7116336, 12018704, 19718181, 31521798, 49228487, 75274584, 112911880, 166423400, 241382700, 344962800, 486301725, 676932006, 931282191, 1267259168
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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FORMULA
| G.f.: P_5(x) / ((1-x)^2*(1-x^2)^2*(1-x^3)^2*(1-x^4)^2*(1-x^5)^2), with P_5(1) = 9!, where P_5(x) = (1+4*x+50*x^2+262*x^3+930*x^4+2566*x^5+5795*x^6+11156*x^7+ 18699*x^8+27712*x^9+36699*x^10+43696*x^11+46988*x^12+45696*x^13+ 40167*x^14+31828*x^15+22603*x^16+14268*x^17+7899*x^18+3762*x^19+ 1498*x^20+474*x^21+110*x^22+16*x^23+x^24).
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PROG
| (PARI) {a(n)=polcoeff(truncate(Ser([1, 4, 50, 262, 930, 2566, 5795, 11156, 18699, 27712, 36699, 43696, 46988, 45696, 40167, 31828, 22603, 14268, 7899, 3762, 1498, 474, 110, 16, 1])) /((1-x)^2*(1-x^2)^2*(1-x^3)^2*(1-x^4)^2*(1-x^5)^2 +x*O(x^n)), n)}
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CROSSREFS
| Cf. A123610 (triangle); columns: A005997, A123613, A123614, A123616.
Sequence in context: A027950 A184447 A053700 * A053535 A039937 A134112
Adjacent sequences: A123612 A123613 A123614 * A123616 A123617 A123618
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KEYWORD
| nonn
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AUTHOR
| Paul D. Hanna (pauldhanna(AT)juno.com), Oct 03 2006
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