A366787 - OEIS

%I #7 Oct 23 2023 20:27:56

%S 1,1,1,1,1,1,1,3,1,1,1,9,1,3,3,1,1,1,1,27,1,9,9,1,1,3,3,3,3,1,1,5,1,1,

%T 1,81,1,27,27,1,1,9,9,3,9,1,1,25,1,3,3,9,3,3,3,5,3,1,1,15,1,5,5,3,1,1,

%U 1,243,1,81,81,1,1,27,27,3,27,1,1,125,1,9,9,9,9,3,3,25,9,1,1,75,1,25,25,9,1,3,3,27

%N a(n) = A366789(A163511(n)).

%H Antti Karttunen, <a href="/A366787/b366787.txt">Table of n, a(n) for n = 0..16383</a>

%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>

%o (PARI)

%o A000265(n) = (n>>valuation(n,2));

%o A163511(n) = if(!n, 1, my(p=2, t=1); while(n>1, if(!(n%2), (t*=p), p=nextprime(1+p)); n >>= 1); (t*p));

%o A366789(n) = { my(f=factor(n)); prod(k=1, #f~, A000265(primepi(f[k, 1]))^f[k, 2]); };

%o A366787(n) = A366789(A163511(n));

%Y Cf. A163511, A366789, A366792.

%Y Cf. also A365426, A365427

%K nonn

%O 0,8

%A _Antti Karttunen_, Oct 23 2023