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%I #12 Sep 04 2017 04:08:46
%S 1,1,3,1,5,23,7,3,3,25,11,1173,13,27,35,31,17,2369,19,12255,37,211,23,
%T 586703,5,213,39,12357,29,23561015,31,1551,311,217,57,117345609,37,
%U 219,313,6145255,41,23671421,43,120561,35915,223,47,2933515203,7,251025,317
%N If n is composite replace n with the concatenation of its nontrivial divisors [ A037279 ] then divide out any factors of 2.
%e Divisors of 12 are 1,2,3,4,6,12, so 12 -> 2346 = 2*1173 -> 1173 = a(12).
%p with(numtheory):ds:=proc(s) local j: RETURN(add(s[j]*10^(j-1),j=1..nops(s))):end: a:=proc(n) options remember: local d,i,l,m: if n<3 then RETURN(1) else if not isprime(n) then d:=divisors(n): l:=nops(d): m:=ds([seq(op(convert(d[l-i+1],base,10)),i=2..l-1)]): RETURN(m/piecewise(m mod 2=1,1,2^(ifactors(m)[2][1][2]))) else RETURN(n) fi fi: end; seq(a(n),n=1..70); # C. Ronaldo
%Y Cf. A037279.
%K nonn,easy,base
%O 1,3
%A _N. J. A. Sloane_
%E More terms from _Erich Friedman_
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