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A369036
a(n) = 1 if A327860(n) is of the form 4m+2, otherwise 0, where A327860 is the arithmetic derivative of the primorial base exp-function.
4
0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0
OFFSET
0
COMMENTS
Asymptotic mean seems to be 1/8. See comments in A369034.
FORMULA
a(n) = [A353630(n) == 2], where [ ] is the Iverson bracket.
a(n) = A121262(n) - A369034(n).
a(n) = A353495(A276086(n)).
PROG
(PARI)
A327860(n) = { my(s=0, m=1, p=2, e); while(n, e = (n%p); m *= (p^e); s += (e/p); n = n\p; p = nextprime(1+p)); (s*m); };
A369036(n) = (2==(A327860(n)%4));
CROSSREFS
Characteristic function of A369037.
Sequence in context: A011669 A023971 A185014 * A354948 A330551 A346618
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 20 2024
STATUS
approved