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%I #18 Jun 26 2018 04:59:19
%S 1,2,4,5,7,9,10,11,13,14,16,18,20,24,28,29,31,32,34,36,37,38,40,41,43,
%T 45,47,51,55,57,59,63,65,69,73,77,85,86,88,90,91,92,94,95,97,99,101,
%U 105,109,110,112,113,115,117,118,119,121,122,124,126,128,132,136,138
%N a(1) = 1; a(n+1) = a(n) + product of nonzero digits of a(n) when written in base 3. But display sequence in base 10.
%H Harry J. Smith, <a href="/A063113/b063113.txt">Table of n, a(n) for n = 1..1000</a>
%H P. A. Loomis, <a href="http://facstaff.bloomu.edu/ploomis/sequences.html">An Interesting Family of Iterated Sequences</a>
%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>
%t f[n_Integer] := (a = Sort[ IntegerDigits[n, 3]]; While[ a[[1]] == 0, a = Delete[a, 1]]; n + Apply[ Times, a] ); NestList[f, 1, 65]
%o (PARI) baseE(x, b)= { local(d,e,f); e=0; f=1; while (x>0, d=x-b*(x\b); x\=b; e+=d*f; f*=10); return(e) }
%o ProdNzD(x)= { local(d,p); p=1; while (x>9, d=x-10*(x\10); if (d, p*=d); x\=10); return(p*x) }
%o { for (n=1, 1000, if (n>1, a=baseE(b+= ProdNzD(a), 3), a=1; b=1); write("b063113.txt", n, " ", b) ) } \\ _Harry J. Smith_, Aug 19 2009
%Y Cf. A063108, A063112, A063114.
%K nonn,base
%O 1,2
%A _N. J. A. Sloane_, Aug 08 2001
%E More terms from _Robert G. Wilson v_, Aug 09 2001
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