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A131955
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a(n) = sum of digits of (n!! + a(n-1)).
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4
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1, 3, 6, 5, 2, 5, 2, 17, 17, 23, 14, 23, 23, 23, 23, 23, 41, 41, 41, 41, 41, 50, 41, 59, 68, 59, 68, 59, 68, 86, 86, 104, 95, 95, 104, 86, 104, 86, 122, 95, 104, 113, 149, 95, 140, 95, 131, 122, 149, 140, 140, 113, 185, 149, 185, 149, 176, 194, 176, 185, 194, 194, 203
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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EXAMPLE
| a(4)=6+4!!=6+8=14 -> Sum_digits(14)=5
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MAPLE
| P:=proc(n) local a, i, k, w; a:=0; for i from 1 by 1 to n do w:=0; k:=a+2^((1+2*i-cos(i*Pi))/4)*Pi^((cos(i*Pi)-1)/4)*GAMMA(1+1/2*i); while k>0 do w:=w+k-(trunc(k/10)*10); k:=trunc(k/10); od; a:=w; print(a); od; end: P(100);
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CROSSREFS
| Cf. A055263, A131954.
Sequence in context: A154008 A144179 A155540 * A019652 A099874 A011223
Adjacent sequences: A131952 A131953 A131954 * A131956 A131957 A131958
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KEYWORD
| easy,nonn,base
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AUTHOR
| Paolo P. Lava & Giorgio Balzarotti (paoloplava(AT)gmail.com), Jul 31 2007
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