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A096941
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Fourth column of (1,5)-Pascal triangle A096940.
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3
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5, 16, 34, 60, 95, 140, 196, 264, 345, 440, 550, 676, 819, 980, 1160, 1360, 1581, 1824, 2090, 2380, 2695, 3036, 3404, 3800, 4225, 4680, 5166, 5684, 6235, 6820, 7440, 8096, 8789, 9520, 10290, 11100, 11951, 12844, 13780, 14760, 15785, 16856, 17974, 19140
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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COMMENTS
| If Y is a 5-subset of an n-set X then, for n>=7, a(n-7) is the number of 3-subsets of X having at most one element in common with Y. - Milan R. Janjic (agnus(AT)blic.net), Dec 08 2007
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FORMULA
| a(n)= (n+15)*(n+2)*(n+1)/6 = 5*b(n)-4*b(n-1), with b(n):=A000292(n)=binomial(n+3, 3).
G.f.: (5-4*x)/(1-x)^4.
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MATHEMATICA
| Table[(n^3 + 15 n^2 + 14 n)/6, {n, 100}] (* From Vladimir Joseph Stephan Orlovsky, Jul 06 2011 *)
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CROSSREFS
| Third column: A056000; fifth column: A096942.
Sequence in context: A038361 A172166 A131425 * A098404 A190970 A077415
Adjacent sequences: A096938 A096939 A096940 * A096942 A096943 A096944
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KEYWORD
| nonn,easy
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AUTHOR
| Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), Jul 16 2004
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