A161178 - OEIS

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A161178

Sum of the double factorials of the digits of n.

1, 1, 2, 3, 8, 15, 48, 105, 384, 945, 2, 2, 3, 4, 9, 16, 49, 106, 385, 946, 3, 3, 4, 5, 10, 17, 50, 107, 386, 947, 4, 4, 5, 6, 11, 18, 51, 108, 387, 948, 9, 9, 10, 11, 16, 23, 56, 113, 392, 953, 16, 16, 17, 18, 23, 30, 63, 120, 399, 960, 49, 49, 50, 51, 56, 63, 96, 153, 432, 993

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Harvey P. Dale, Table of n, a(n) for n = 0..1000

EXAMPLE

a(24) = (2!!) + (4!!) = 2 + 8 = 10. a(35) = (3!!) + (5!!) = 3 + 15 = 18.

MAPLE

A161178 := proc(n) if n = 0 then 1; else add(doublefactorial(d), d=convert(n, base, 10)) ; end if; end proc:

MATHEMATICA

Total[IntegerDigits[#]!!]&/@Range[0, 70] (* Harvey P. Dale, Aug 28 2013 *)

CROSSREFS