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A084940
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Heptagorials: n-th polygorial for k=7.
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14
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1, 1, 7, 126, 4284, 235620, 19085220, 2137544640, 316356606720, 59791398670080, 14050978687468800, 4018579904616076800, 1374354327378698265600, 553864793933615401036800, 259762588354865623086259200
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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FORMULA
| A084940(n) = Polygorial(n, 7) = A000142(n)/A000079(n)*A047055(n) = n!/2^n*product(5*i+2, i=0..n-1) = n!/2^n*5^n*pochhammer(2/5, n) = n!/2^n*5^n*GAMMA(n+2/5)*sin(2*Pi/5)*GAMMA(3/5)/Pi
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MAPLE
| a := n->n!/2^n*mul(5*i+2, i=0..n-1); [seq(a(j), j=0..30)];
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CROSSREFS
| Cf. A006472, A001044, A000680, A084939, A084941, A084942, A084943, A084944, A085356.
Sequence in context: A180583 A202798 A204248 * A139987 A061744 A053716
Adjacent sequences: A084937 A084938 A084939 * A084941 A084942 A084943
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KEYWORD
| easy,nonn
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AUTHOR
| Daniel Dockery (peritus(AT)gmail.com) Jun 13 2003
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