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A089145
Greatest common divisor of n^2-3 and n^2+3.
3
3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1
OFFSET
0,1
FORMULA
From Colin Barker, Dec 11 2019: (Start)
G.f.: (3 + 2*x + x^2 + 6*x^3 + x^4 + 2*x^5) / ((1 - x)*(1 + x)*(1 - x + x^2)*(1 + x + x^2)).
a(n) = a(n-6) for n>5.
(End)
PROG
(PARI) g(n) = for(x=0, n, print1(gcd(x^2-3, x^2+3)", "))
(PARI) Vec((3 + 2*x + x^2 + 6*x^3 + x^4 + 2*x^5) / ((1 - x)*(1 + x)*(1 - x + x^2)*(1 + x + x^2)) + O(x^80)) \\ Colin Barker, Dec 11 2019
CROSSREFS
Sequence in context: A248033 A318254 A002130 * A324644 A364256 A361470
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Dec 05 2003
STATUS
approved