%I #11 Nov 29 2013 21:00:47
%S 3,6,12,14,18,26,38,62,74,102,104,108,116,122,126,138,162,174,202,206,
%T 218,234,258,338,410,414,430,442,474,586,826,922,958,1318,1342,1366,
%U 1474,1586,1826,1922,1958,2318,2366,2582,2742,2854,3174,3258,3498,4362,4506
%N a(1) = 3; thereafter a(n+1) = a(n) + product of nonzero digits of a(n).
%H P. A. Loomis, <a href="http://facstaff.bloomu.edu/ploomis/itseq4.ps">An Introduction to Digit Product Sequences</a>, J. Rec. Math., 32 (2003-2004), 147-151.
%H P. A. Loomis, <a href="/A063108/a063108.pdf">An Introduction to Digit Product Sequences</a>, J. Rec. Math., 32 (2003-2004), 147-151. [Annotated archived copy]
%H <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>
%p f:=proc(n) local t1,t2,i;
%p t1:=convert(n,base,10);
%p t2:=1;
%p for i from 1 to nops(t1) do if t1[i] <> 0 then t2:=t2*t1[i]; fi; od;
%p t2; end;
%p g:=n->n+f(n);
%p t1:=[3];
%p for n from 1 to 50 do t1:=[op(t1),g(t1[nops(t1)])]; od:
%p t1;
%Y Cf. A063018, A232485, A232487, A232488.
%K nonn,base
%O 1,1
%A _N. J. A. Sloane_, Nov 29 2013
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