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A112415
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C(1+n,1)*C(2+n,1)*C(4+n,2).
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2
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12, 60, 180, 420, 840, 1512, 2520, 3960, 5940, 8580, 12012, 16380, 21840, 28560, 36720, 46512, 58140, 71820, 87780, 106260, 127512, 151800, 179400, 210600, 245700, 285012, 328860, 377580, 431520
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 0..680
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FORMULA
| a(n)=(n+1)(n+2)(n+3)(n+4)/2=A033486(n+1)=12*A000332(n+4). O.g.f.: 12/(1-x)^5. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 15 2008]
a(0)=12, a(1)=60, a(2)=180, a(3)=420, a(4)=840, a(n)=5*a(n-1)- 10*a(n-2)+ 10*a(n-3)-5*a(n-4)+a(n-5) [From Harvey P. Dale, Jul 24 2011]
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EXAMPLE
| If n=0 then C(1+0,1)*C(2+0,1)*C(4+0,2)= C(1,1)*C(2,1)*C(4,2)=1*2*6=12
if n=10 then C(1+10,1)*C(2+10,1)*C(4+10,2)= C(11,1)*C(12,1)*C(14,2)=11*12*91=12012
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MATHEMATICA
| Table[(n+1)(n+2)Binomial[4+n, 2], {n, 0, 30}] (* or *) LinearRecurrence[ {5, -10, 10, -5, 1}, {12, 60, 180, 420, 840}, 31] (* From Harvey P. Dale, Jul 24 2011 *)
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PROG
| (MAGMA) [(n+1)*(n+2)*(n+3)*(n+4)/2: n in [0..40]]; // Vincenzo Librandi, Apr 28 2011
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CROSSREFS
| Sequence in context: A000141 A008530 A033486 * A174642 A061624 A004302
Adjacent sequences: A112412 A112413 A112414 * A112416 A112417 A112418
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KEYWORD
| easy,nonn
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AUTHOR
| Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Dec 09 2005
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