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%I #32 Oct 30 2015 04:46:59
%S 1,3,4,6,12,60,5040,293318625600,
%T 635197862493622653217009501211465321419691071212633792891415680000000000
%N Position of first occurrence of n in A036459.
%e For n=7, a(7) = 293318625600 -> 5040 -> 60 -> 12 -> 6 -> 4 -> 3 -> 2.
%e For n=8, a(8) -> 1111523212800 -> 5040 -> 60 -> 12 -> 6 -> 4 -> 3 -> 2.
%o (PARI) a036459(n) = {if (n<=2, return(0)); nb = 1; while ((nd = numdiv(n)) > 2, n = nd; nb++); nb;}
%o a(n) = {k = 1; while (a036459(k) != n, k++); k;} \\ _Michel Marcus_, Oct 28 2015
%Y Coincides with A009287 for n <= 7 (only).
%K nonn
%O 0,2
%A _Ivan Neretin_, Mar 29 2015
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