A265182 - OEIS

%I #23 Dec 06 2015 10:34:48

%S 1,0,0,0,0,0,0,0,0,3,3,5,5,5,5,5,5,5,5,0,5,0,0,1,1,0,0,0,0,0,5,0,0,0,

%T 0,1,0,0,1,0,5,1,0,0,0,0,0,0,0,0,5,0,0,0,0,0,0,0,0,0,5,0,0,0,0,0,0,0,

%U 0,0,5,0,0,0,0,0,0,0,0,0,5,0,0,0,0,0

%N Base-10 analog of Marko Riedel's A265008.

%H Reinhard Zumkeller, <a href="/A265182/b265182.txt">Table of n, a(n) for n = 1..10000</a>

%p F:= proc(n) local L, ss;

%p   L:= convert(n, base, 10);

%p   ss:= {seq(seq(add(10^(i-j)*L[i], i=j..k), j=1..k), k=1..nops(L))} minus {0};

%p   numboccur(true, [seq(seq(member(a*b, ss), a=ss), b=ss)]);

%p end proc:

%p seq(F(n), n=1..1000); # _Robert Israel_, Dec 06 2015

%o (Haskell)

%o a265182 n = length [() | let cs = dropWhile (== 0) $ a218978_row n, c <- cs,

%o             let as = takeWhile (<= c) cs, a <- as, b <- as, a * b == c]

%o -- _Reinhard Zumkeller_, Dec 05 2015

%Y Cf. A265008, A265236.

%Y See A265183 for the version where A, B, C may be zero.

%Y Cf. A218978.

%K nonn,base

%O 1,10

%A _N. J. A. Sloane_, Dec 04 2015

%E Corrected by _Lars Blomberg_, Dec 05 2015