A373141 a(n) = 1 if A276085(n) is of the form 4m+2, otherwise 0, where A276085 is the primorial base log-function.

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

Offset

1

Links

Antti Karttunen, Table of n, a(n) for n = 1..100000

Index entries for characteristic functions

Index entries for sequences computed from indices in prime factorization

Index entries for sequences related to primorial numbers

Formula

a(n) = [A276085(n) == 2 (mod 4)], where [ ] is the Iverson bracket.

a(n) = A035263(n) - A369001(n).

Prog

(PARI)
A002110(n) = prod(i=1, n, prime(i));
A276085(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*A002110(primepi(f[k, 1])-1)); };
A373141(n) = (2==(A276085(n)%4));

Crossrefs

Characteristic function of A373142.

Cf. A002110, A035263, A276085, A369001.

Sequence in context: A285159 A073089 A373470 * A323158 A011657 A354896

Adjacent sequences: A373138 A373139 A373140 * A373142 A373143 A373144

Keyword

nonn

Author

Antti Karttunen, May 26 2024

Status

approved