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%I #13 Jul 29 2017 19:19:48
%S 1,2,2,1,2,2,2,1,1,2,2,3,2,2,2,1,2,3,2,3,2,2,2,2,1,2,1,3,2,2,2,1,2,2,
%T 2,1,2,2,2,2,2,2,2,3,3,2,2,2,1,3,2,3,2,2,2,2,2,2,2,3,2,2,3,1,2,2,2,3,
%U 2,2,2,1,2,2,3,3,2,2,2,2,1,2,2,3,2,2,2,2,2,3,2,3,2,2,2,2,2,3,3,1,2,2,2,2,2,2
%N a(1) = 1; for n>1, a(n) = the smallest positive integer not occurring among the exponents in the prime-factorization of n.
%H Antti Karttunen, <a href="/A134193/b134193.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>
%F a(n) = A257993(A181819(n)). - _Antti Karttunen_, Jul 28 2017
%e The prime factorization of 24 is 2^3 * 3^1. The exponents are 3 and 1. Therefore a(24) = 2 is the smallest positive integer not occurring among (3,1).
%t Table[Complement[Range[n], Table[FactorInteger[n][[i, 2]], {i, 1, Length[FactorInteger[n]]}]][[1]], {n, 2, 120}] (* _Stefan Steinerberger_, Jan 21 2008 *)
%o (Scheme) (define (A134193 n) (A257993 (A181819 n))) ;; _Antti Karttunen_, Jul 28 2017
%o (PARI) a(n) = if (n==1, 1, my(f=factor(n)); ve = vecsort(f[,2],,8); k = 1; while(vecsearch(ve, k), k++); k;); \\ _Michel Marcus_, Jul 28 2017
%Y Cf. A136567, A181819, A257993.
%K nonn
%O 1,2
%A _Leroy Quet_, Jan 13 2008
%E More terms from _Stefan Steinerberger_, Jan 21 2008
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