cp's OEIS Frontend

A334319 Number of integers m in base n with distinct digits such that the number formed by the consecutive subsequence of the initial j digits is divisible by j for all j in {1,...,length(m)}.

%I A334319 #17 May 04 2020 14:25:09
%S A334319 1,3,4,16,18,54,112,225,397,707,1566,2664,6960,9213,23066,39980,
%T A334319 100239,116229,455539,465054,1157163,2064246,6735123,4609476,22943866,
%U A334319 27085154,64108419,76354062,420698429,180541932,1833215296,1057775180,3361833346,5293490772,14955881506,7186246508
%N A334319 Number of integers m in base n with distinct digits such that the number formed by the consecutive subsequence of the initial j digits is divisible by j for all j in {1,...,length(m)}.
%p A334319 b:= proc(n, s, w) option remember; `if`(s={}, 0, (k-> add((t->
%p A334319       `if`(t=0, 1, `if`(irem(t, k)=0, b(n, s minus {j}, t)
%p A334319           +1, 0)))(w*n+j), j=s)))(1+n-nops(s))
%p A334319     end:
%p A334319 a:= n-> b(n, {$0..n-1}, 0):
%p A334319 seq(a(n), n=1..18);
%Y A334319 Row sums of A334318.
%K A334319 nonn,base
%O A334319 1,2
%A A334319 _Alois P. Heinz_, Apr 22 2020
%E A334319 a(27)-a(36) from _Giovanni Resta_, May 04 2020