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 A162747 A factorial-Pascal matrix. 1
 1, 1, 1, 1, 3, 1, 1, 6, 6, 1, 1, 10, 20, 10, 1, 1, 15, 50, 50, 15, 1, 1, 21, 105, 176, 105, 21, 1, 1, 28, 196, 497, 497, 196, 28, 1, 1, 36, 336, 1204, 1830, 1204, 336, 36, 1, 1, 45, 540, 2604, 5634, 5634, 2604, 540, 45, 1, 1, 55, 825, 5160, 15150, 21642, 15150, 5160, 825 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 COMMENTS Row sums are A162748. LINKS FORMULA Number triangle T(n,k)=sum{j=0..n, C(n,j)*C(n-j,2(k-j))*if(j<=k,(k-j)!,0)}. G.f.: 1/(1-x-xy-x^2*y/(1-x-xy-x^2*y/(1-x-xy-2x^2*y/(1-x-xy-2x^2*y/(1-x-xy-3x^2*y/(1-... (continued fraction). [From Paul Barry, Apr 12 2010] EXAMPLE Triangle begins 1, 1, 1, 1, 3, 1, 1, 6, 6, 1, 1, 10, 20, 10, 1, 1, 15, 50, 50, 15, 1, 1, 21, 105, 176, 105, 21, 1, 1, 28, 196, 497, 497, 196, 28, 1, 1, 36, 336, 1204, 1830, 1204, 336, 36, 1, 1, 45, 540, 2604, 5634, 5634, 2604, 540, 45, 1, 1, 55, 825, 5160, 15150, 21642, 15150, 5160, 825, 55, 1 CROSSREFS Sequence in context: A056241 A162745 A001263 * A107105 A088925 A100862 Adjacent sequences:  A162744 A162745 A162746 * A162748 A162749 A162750 KEYWORD easy,nonn,tabl AUTHOR Paul Barry, Jul 12 2009 STATUS approved

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Last modified January 21 19:57 EST 2019. Contains 319350 sequences. (Running on oeis4.)