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A326281
Let f(n) be a sequence of distinct Gaussian integers such that f(1) = 0 and for any n > 1, f(n) = f(floor(n/2)) + k(n)*g((1+i)^(A000120(n)-1) * (1-i)^A023416(n)) where k(n) > 0 is as small as possible and g(z) = z/gcd(Re(z), Im(z)); a(n) is the imaginary part of f(n).
2
0, -1, 1, -2, -1, 1, 2, -3, -3, -2, 0, -1, 2, 3, 3, -3, -4, -4, -3, -4, -2, 0, 1, -3, -1, 2, 3, 3, 4, 4, 3, -2, -4, -5, -5, -6, -5, -4, 0, -5, -5, -3, 1, -2, 1, 3, 2, -6, -4, -3, 2, -1, 4, 4, 5, 2, 4, 5, 6, 6, 5, 4, 2, -1, -2, -4, -5, -5, -6, -7, -5, -6, -7
OFFSET
1,4
PROG
(PARI) See Links section.
CROSSREFS
See A326280 for the real part of f and additional comment.
Sequence in context: A285554 A128495 A328062 * A343026 A113136 A156267
KEYWORD
sign,look
AUTHOR
Rémy Sigrist, Jun 22 2019
STATUS
approved