A331170 - OEIS

%I #7 Jan 12 2020 23:50:26

%S 1,2,3,3,5,6,7,5,9,10,11,10,13,14,15,7,17,15,19,20,21,22,23,14,25,26,

%T 25,28,29,30,31,11,33,34,35,21,37,38,39,28,41,42,43,44,45,46,47,22,49,

%U 45,51,52,53,35,55,56,57,58,59,42,61,62,63,13,65,66,67,68,69,70,71,33,73,74,75,76,77,78,79,44,49,82,83,84,85,86,87,88,89,70,91,92,93,94,95,26,97,98,99,63

%N a(n) = min(n, A122111(n)), where A122111 conjugates the prime factorization of n.

%C For all i, j:

%C   a(i) = a(j) => A056239(i) = A056239(j),

%C   a(i) = a(j) => A243503(i) = A243503(j).

%H Antti Karttunen, <a href="/A331170/b331170.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%o (PARI)

%o A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};

%o A122111(n) = if(1==n,n,prime(bigomega(n))*A122111(A064989(n)));

%o A331170(n) = min(n, A122111(n));

%Y Cf. A056239, A064989, A122111, A243503.

%K nonn

%O 1,2

%A _Antti Karttunen_, Jan 12 2020