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A197169 Values of gcd(n,y) for successive y = A197128(n). 1
2, 2, 2, 2, 2, 2, 2, 46, 2, 2, 2, 2, 3, 10, 6, 2, 3, 3, 2, 2, 2, 6, 5, 2, 2, 5, 2, 2, 2, 2, 2, 2, 22, 5, 2, 2, 3, 2, 2, 3, 2, 2, 3, 46, 5, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 14, 2, 4, 3, 2, 2, 2, 4, 14, 3, 2, 3, 2, 5, 2, 2, 2, 5, 2, 2, 2, 3, 6, 29, 3, 2, 2, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..84.

MATHEMATICA

cr = {}; Do[If[IntegerQ[Sqrt[n]], , kk = NumberFieldFundamentalUnits[Sqrt[n]]; d1 = kk[[1]][[2]][[1]]; d2 = kk[[1]][[1]] kk[[1]][[2]][[2]]; d4 = Numerator[d2/Sqrt[n]]; If[GCD[d4, n] == 1, , AppendTo[cr, GCD[d4, n]]]], {n, 2, 20000}]; cr

CROSSREFS

Cf. A087643, A172000, A194366, A197115, A197127, A197128.

Sequence in context: A248771 A291721 A109913 * A048052 A184156 A187785

Adjacent sequences:  A197166 A197167 A197168 * A197170 A197171 A197172

KEYWORD

nonn

AUTHOR

Artur Jasinski, Oct 11 2011

STATUS

approved

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Last modified July 10 13:04 EDT 2020. Contains 335576 sequences. (Running on oeis4.)