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A331003
a(n) is the imaginary part of f(n) (as defined in A330779).
2
0, 1, 1, -1, -1, 2, 2, -2, -2, 2, 2, -2, -2, 3, 3, -3, -3, 2, 2, -4, -4, 3, 3, -3, -3, 4, 4, -3, -3, 4, 4, -4, -4, 4, 4, -5, -5, 3, 3, -5, -5, 5, 5, -6, -6, 3, 3, -6, -6, 4, 4, -5, -5, 5, 5, -6, -6, 6, 6, -7, -7, 3, 3, -7, -7, 5, 5, -6, -6, 5, 5, -6, -6, 5, 5
OFFSET
0,6
LINKS
FORMULA
a(2*k+2) = a(2*k+1) for any k >= 0.
a(2*k+1) = a(2*k) + A330779(2*k+1) * (-1)^k for any k >= 0.
PROG
(PARI) See Links section.
CROSSREFS
Cf. A330779.
Sequence in context: A209253 A165113 A069903 * A086007 A108582 A345378
KEYWORD
sign
AUTHOR
Rémy Sigrist, Jan 05 2020
STATUS
approved