A324398 a(1) = 0; for n > 1, a(n) = A318458(A156552(n)).

0, 0, 0, 1, 0, 1, 0, 1, 6, 0, 0, 1, 0, 1, 8, 9, 0, 1, 0, 1, 16, 1, 0, 1, 0, 1, 10, 1, 0, 1, 0, 1, 0, 1, 20, 9, 0, 1, 66, 1, 0, 1, 0, 1, 6, 1, 0, 1, 0, 0, 2, 1, 0, 1, 36, 1, 258, 1, 0, 1, 0, 1, 6, 41, 0, 1, 0, 1, 0, 1, 0, 17, 0, 1, 16, 1, 32, 1, 0, 1, 10, 1, 0, 1, 132, 1, 1026, 1, 0, 33, 72, 1, 0, 1, 256, 25, 0, 0, 66, 17, 0, 1, 0, 1, 34

Offset: 1

Author

Antti Karttunen, Mar 05 2019

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..4473
• Index entries for sequences related to binary expansion of n
• Index entries for sequences computed from indices in prime factorization
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A000203, A156552, A318458, A323243, A323244, A324396, A324397.

Programs

PARI

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)};
A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n))));
A318458(n) = bitand(n, sigma(n)-n);
A324398(n) = if(1==n,0,A318458(A156552(n)));

Formula

a(1) = 0; for n > 1, a(n) = A318458(A156552(n)).

a(n) = A156552(n) AND (A323243(n) - A156552(n)).