login
A341346
a(n) = A048673(2n-1) mod 3.
8
1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0
OFFSET
1
COMMENTS
Characteristic function of A341349.
FORMULA
a(n) = A341345(2n-1) = A010872(A254049(n)) = A010872(A048673(2n-1)).
a(n) = [A292251(2n-1) == 0], where [ ] is the Iverson bracket.
PROG
(PARI)
A003961(n) = { my(f=factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); }; \\ From A003961
A341346(n) = (((A003961(n+n-1)+1)/2)%3);
CROSSREFS
Bisection of A341345.
Cf. A341348 (runlengths), A341349 (positions of ones), A341350 (of zeros).
Sequence in context: A106346 A296212 A189921 * A167371 A127241 A087748
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 09 2021
STATUS
approved