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 A319563 Let f(1) = 1, f(2) = 1 + i (where i denotes the imaginary unit), and for n > 1, f(n+1) is the Gaussian integer in the first quadrant (with positive real part and nonnegative imaginary part) with least modulus and sharing a prime factor with f(n) (in case of a tie, minimize the imaginary part); a(n) = the imaginary part of f(n). 2
 0, 1, 0, 2, 1, 2, 4, 3, 1, 2, 0, 3, 0, 0, 1, 3, 6, 5, 2, 4, 4, 3, 4, 8, 5, 1, 2, 2, 0, 3, 6, 3, 4, 6, 1, 5, 7, 3, 5, 10, 7, 2, 4, 0, 6, 5, 6, 12, 7, 1, 2, 4, 7, 1, 4, 8, 2, 6, 9, 8, 1, 5, 10, 9, 4, 8, 3, 0, 9, 7, 0, 0, 0, 7, 6, 8, 2, 10, 5, 7, 14, 9, 2, 4, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS See A319561 for the square of the modulus of f and additional comments. LINKS Rémy Sigrist, Table of n, a(n) for n = 1..10000 Rémy Sigrist, PARI program for A319563 PROG (PARI) See Links section. CROSSREFS Cf. A319561. Sequence in context: A262876 A263045 A333442 * A201912 A201908 A256184 Adjacent sequences:  A319560 A319561 A319562 * A319564 A319565 A319566 KEYWORD nonn AUTHOR Rémy Sigrist, Sep 23 2018 STATUS approved

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Last modified May 30 18:07 EDT 2020. Contains 334728 sequences. (Running on oeis4.)