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 A136660 Unsigned fourth column (k=3) of triangle A136656 divided by 8. 3
 1, 18, 255, 3465, 47880, 687960, 10372320, 164656800, 2754259200, 48518870400, 899026128000, 17495593315200, 356995102464000, 7625049239808000, 170196434343936000, 3963602854987776000, 96160451873181696000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Also unsigned third column of triangle A136657 divided by 4. REFERENCES Ch. A. Charalambides, Enumerative Combinatorics, Chapman & Hall/CRC, Boca Raton, Florida, 2002, Table 8.3, p. 311, with s=-2, k=3 column/8. LINKS FORMULA a(n)= |A136656(n+3,3)|/8, n>=0. E.g.f.(derived from the one given for the column k=3 under A136656): (2+18*x+3*x^2-12*x^3+3*x^4)/(2*(1-x)^9). CROSSREFS Cf. A136659 (column k=2), A136661 (column k=4). Sequence in context: A062141 A157708 A159537 * A255372 A255373 A255374 Adjacent sequences:  A136657 A136658 A136659 * A136661 A136662 A136663 KEYWORD nonn,easy AUTHOR Wolfdieter Lang Feb 22 2008 STATUS approved

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Last modified March 29 15:16 EDT 2020. Contains 333107 sequences. (Running on oeis4.)