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

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

Cf. A061602, A006882.

Sequence in context: A148010 A148011 A148012 * A006882 A080498 A148013

Adjacent sequences: A161175 A161176 A161177 * A161179 A161180 A161181

Keyword

easy,nonn,base

Author

Paolo P. Lava and Giorgio Balzarotti, Jun 05 2009

Status

approved