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A020040 a(n) = round( Gamma(n+1/5)/Gamma(1/5) ). 2
1, 0, 0, 1, 2, 7, 37, 229, 1647, 13507, 124269, 1267543, 14196477, 173197024, 2286200718, 32464050199, 493453563029, 7993947721071, 137495900802424, 2502425394604114, 48046567576398986, 970540665043259525 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Gamma(n+1/5)/Gamma(1/5) = 1, 1/5, 6/25, 66/125, 1056/625, 22176/3125, 576576/15625, 17873856/78125, ... - R. J. Mathar, Sep 04 2016

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..450

MAPLE

Digits := 64:f := proc(n, x) round(GAMMA(n+x)/GAMMA(x)); end;

seq( round(pochhammer(1/5, n)), n=0..30); # G. C. Greubel, Dec 06 2019

MATHEMATICA

Table[Round[Pochhammer[1/5, n]], {n, 0, 30}] (* G. C. Greubel, Dec 06 2019 *)

PROG

(PARI) x=1/5; vector(30, n, round(gamma(n-1+x)/gamma(x)) ) \\ G. C. Greubel, Dec 06 2019

(MAGMA) [Round(Gamma(n+1/5)/Gamma(1/5)): n in [0..30]]; // G. C. Greubel, Dec 06 2019

(Sage) [round(rising_factorial(1/5, n)) for n in (0..30)] # G. C. Greubel, Dec 06 2019

CROSSREFS

Cf. A008548, A020085, A020130.

Sequence in context: A062394 A245902 A063766 * A125191 A300559 A302859

Adjacent sequences:  A020037 A020038 A020039 * A020041 A020042 A020043

KEYWORD

nonn

AUTHOR

Simon Plouffe

STATUS

approved

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Last modified February 29 08:26 EST 2020. Contains 332355 sequences. (Running on oeis4.)