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A077544
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Product of next n numbers + sum of next n numbers.
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0
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2, 11, 135, 5074, 360425, 39070191, 5967561775, 1220096909060, 321570878429169, 106137499051584505, 42873948150095463071, 20803502274492921984870, 11938961126118491232769105, 7998487694738166709923841379
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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FORMULA
| a(n) = (k+1)(k+2)...(k+n) + nk + n(n+1)/2, k = n(n-1)/2
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MAPLE
| seq(product(i, i=n*(n-1)/2+1..n*(n-1)/2+n)+n*(n+1)/2+n*(n-1)/2*n, n=1..20);
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MATHEMATICA
| nx[n_]:=Module[{trn=(n(n+1))/2, r}, r=Range[trn-n+1, trn]; Total[r]+ Times@@r]; Array[nx, 20] (* From Harvey P. Dale, Jan 03 2012 *)
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CROSSREFS
| Sequence in context: A066382 A139387 A041725 * A087480 A060059 A177753
Adjacent sequences: A077541 A077542 A077543 * A077545 A077546 A077547
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KEYWORD
| nonn
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Nov 09 2002
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EXTENSIONS
| More terms from Sascha Kurz (sascha.kurz(AT)uni-bayreuth.de), Jan 12 2003
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