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A123613
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Column 3 of triangle A123610.
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4
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1, 4, 20, 68, 175, 392, 786, 1440, 2475, 4036, 6292, 9464, 13805, 19600, 27200, 36996, 49419, 64980, 84238, 107800, 136367, 170696, 211600, 260000, 316881, 383292, 460404, 549460, 651775, 768800, 902066, 1053184, 1223915, 1416108, 1631700
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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FORMULA
| G.f.: P_3(x) / ((1-x)^2*(1-x^2)^2*(1-x^3)^2), with P_3(1) = 5!, where P_3(x) = (1+2*x+11*x^2+26*x^3+30*x^4+26*x^5+17*x^6+6*x^7+x^8).
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PROG
| (PARI) {a(n)=polcoeff(truncate(Ser([1, 2, 11, 26, 30, 26, 17, 6, 1]))/((1-x)^2*(1-x^2)^2*(1-x^3)^2 +x*O(x^n)), n)}
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CROSSREFS
| Cf. A123610 (triangle); columns: A005997, A123614, A123615, A123616.
Sequence in context: A131479 A194094 A055538 * A006740 A197426 A061981
Adjacent sequences: A123610 A123611 A123612 * A123614 A123615 A123616
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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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