A324824 a(n) = 1 if n>1 and sigma(A156552(n)) is congruent to 2 modulo 4, otherwise a(n) = 0.

0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0

Offset

1

Links

Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)

Index entries for sequences related to binary expansion of n

Index entries for characteristic functions

Index entries for sequences computed from indices in prime factorization

Index entries for sequences related to sigma(n)

Prog

(PARI)
A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552 by David A. Corneth
A324824(n) = ((n>1)&&(2==(sigma(A156552(n))%4)));
(PARI) A324824(n) = (2==(A323243(n)%4)); \\ This needs code also from A323243.

Crossrefs

Characteristic function of A324814.

Cf. A156552, A191217, A324822, A324823.

Sequence in context: A341619 A302049 A078926 * A025458 A286925 A179527

Adjacent sequences: A324821 A324822 A324823 * A324825 A324826 A324827

Keyword

nonn

Author

Antti Karttunen, Mar 16 2019

Status

approved