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A246260 a(n) = 1 if A003961(n) is of the form 4k+1, otherwise a(n) = 0, (when A003961(n) is of the form 4k+3). [A003961 is fully multiplicative with a(p) = nextprime(p)]. 10
1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET
1
LINKS
FORMULA
a(n) = A000035(A048673(n)).
a(n) = 1 - A000035((A003961(n)-1)/2).
a(n^2) = 1 for all n >= 1. - Antti Karttunen, Apr 08 2022
PROG
(PARI) A246260(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); (((1+factorback(f))/2)%2); }; \\ Antti Karttunen, Apr 08 2022
(Scheme, two versions)
(define (A246260 n) (A000035 (A048673 n)))
(define (A246260 n) (- 1 (A000035 (/ (- (A003961 n) 1) 2))))
CROSSREFS
Characteristic function of A246261.
Cf. A000035, A003961, A048673, A246262 (partial sums), A246271.
Cf. also A341346.
Sequence in context: A185295 A214295 A145377 * A275973 A218173 A068426
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 21 2014
STATUS
approved

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Last modified March 28 05:39 EDT 2024. Contains 371235 sequences. (Running on oeis4.)