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A225891 Numbers obtained by rotating left the indices in the prime signature of n. 5

%I

%S 1,2,3,4,5,6,7,8,9,10,11,18,13,14,15,16,17,12,19,50,21,22,23,54,25,26,

%T 27,98,29,30,31,32,33,34,35,36,37,38,39,250,41,42,43,242,75,46,47,162,

%U 49,20,51,338,53,24,55,686,57,58,59,150,61,62,147,64,65,66

%N Numbers obtained by rotating left the indices in the prime signature of n.

%C Inverse permutation to A105119.

%C A072774 gives the fixed points.

%C The first term which is different from A105119 is a(60).

%C The first term which is different from A069799 is a(90).

%H Paul Tek, <a href="/A225891/b225891.txt">Table of n, a(n) for n = 1..10000</a>

%e a(2250) = a(2*3^2*5^3) = 2^2*3^3*5 = 540.

%t Table[Times @@ ((ar = Transpose[FactorInteger[n]])[[1]]^RotateLeft[ar[[2]]]), {n, 66}] (* _Ivan Neretin_, Jul 09 2015 *)

%o (PARI) { a(n)=my(f=factor(n),l=#f[,1]);

%o return(prod(i=1,l,f[i,1]^f[if(i==l,1,i+1),2])) }

%Y Cf. A105119, A072774, A069799.

%K nonn

%O 1,2

%A _Paul Tek_, May 20 2013

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Last modified September 24 21:05 EDT 2021. Contains 347651 sequences. (Running on oeis4.)