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%I #15 Aug 27 2020 03:36:44
%S 1,2,4,8,15,16,24,27,32,36,40,48,54,56,60,63,64,72,80,84,90,96,104,
%T 105,108,112,120,128,132,135,140,144,147,152,156,160,164,165,168,180,
%U 189,192,195,200,204,210,216,220,224,225,228,231,240,243,250,252,256
%N Numbers m such that m divides the number of divisors of m!!.
%C It seems that a(n) is asymptotic to c*n with c = 4.8...
%H Amiram Eldar, <a href="/A277166/b277166.txt">Table of n, a(n) for n = 1..10000</a>
%F A114338(a(n)) mod a(n) = 0.
%e 8 is in the sequence because the number of divisor of 8!! is A114338(8) = 16, which is divisible by 8.
%t ok[n_] := Divisible[ DivisorSigma[0, n!!], n]; Select[ Range[200], ok]
%o (PARI) isok(n) = (numdiv(prod(i=0, (n-1)\2, n - 2*i)) % n) == 0; \\ after first Pari in A006882; _Michel Marcus_, Oct 02 2016
%Y Cf. A000005, A006882, A051178, A114338.
%K nonn
%O 1,2
%A _Michel Lagneau_, Oct 01 2016
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