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 A129981 Sum of n!!, with n>=0. 3
 1, 2, 4, 7, 15, 30, 78, 183, 567, 1512, 5352, 15747, 61827, 196962, 842082, 2869107, 13191027, 47650452, 233445012, 888174087, 4604065287, 18353375862, 100102982262, 416337125487, 2378327679087, 10284181259712, 61295935653312 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Partial sums of A006882. LINKS EXAMPLE 0!!=1 1!!=1 -> 1+1=2 2!!=2 -> 2+2=4 3!!=3 -> 4+3=7 4!!=8 -> 7+8=15 5!!=15 -> 15+15=30 MAPLE A129981 := proc(n)         add(doublefactorial(m), m=0..n) ; end proc: # R. J. Mathar, Oct 11 2011 MATHEMATICA s = 0; lst = {}; Do[s += n!!; AppendTo[lst, s], {n, 0, 26, 1}]; lst (* Zerinvary Lajos, Jul 10 2009 *) CROSSREFS Sequence in context: A115178 A049885 A129682 * A072964 A247291 A030033 Adjacent sequences:  A129978 A129979 A129980 * A129982 A129983 A129984 KEYWORD easy,nonn AUTHOR Paolo P. Lava and Giorgio Balzarotti, Jun 14 2007 STATUS approved

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Last modified May 26 04:46 EDT 2019. Contains 323579 sequences. (Running on oeis4.)