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%I #8 Aug 20 2021 04:21:24
%S 1,2,3,4,6,9,51,57,252,585,1131,2106,2172,2250,2292,26159,26769,27253,
%T 28071,46802,47148,48018
%N Numbers k that divide the sum of the digits of k!!, the double factorial of k.
%C Next term after 48018, if it exists, is greater than 100000.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/DoubleFactorial.html">Double Factorial</a>.
%e 585 is a term because the sum of the digits of 585!! = 2925 is divisible by 585.
%t Do[If[Mod[Plus @@ IntegerDigits[n!! ], n] == 0, Print[n]], {n, 1, 100000}]
%Y Cf. A006882.
%K nonn,base,hard,more
%O 1,2
%A _Ryan Propper_, Jul 11 2005
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