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A053373 Write fundamental unit for real quadratic field of discriminant n as x + y*omega; sequence gives values of y for n == 1 (mod 4). 1
1, 1, 2, 1, 1, 8, 2, 10, 1, 40, 5, 2, 3, 250, 1, 1, 106, 3, 1138, 2, 8, 25, 146, 2968, 15, 298, 16, 2, 5, 17, 1856, 1, 1, 9384, 97, 10, 253970, 2, 72664, 3, 6440, 5, 521904, 1, 1, 3034, 5, 9148450, 1084152, 117, 2, 746, 10, 88, 157, 126890, 1, 1, 1311, 56, 287 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Entries are indexed by values of n from A039955.

Subsequence of A077058 excluding terms for which A077425(n) is not squarefree. - Max Alekseyev, Dec 12 2012

REFERENCES

R. A. Mollin, Quadratics, CRC Press, 1996, Tables B1-B3.

LINKS

Emmanuel Vantieghem, Table of n, a(n) for n=1..1000

S. R. Finch, Class number theory

MATHEMATICA

2*NumberFieldFundamentalUnits[ Sqrt[#] ][[1, 2, 2]] & /@ Select[ Range[5, 309, 4], SquareFreeQ ]  (* Jean-Fran├žois Alcover, Jul 09 2013 *)

PROG

(PARI) forstep(n=5, 1000, 4, if(!issquarefree(n), next); print1( 2*polcoeff(lift(bnfinit(x^2-n).fu[1]), 1), ", " )) /* Max Alekseyev */

CROSSREFS

Cf. A053370-A053375.

Sequence in context: A134470 A119418 A077058 * A297733 A255812 A249141

Adjacent sequences:  A053370 A053371 A053372 * A053374 A053375 A053376

KEYWORD

nonn,easy,nice

AUTHOR

N. J. A. Sloane, Jan 06 2000

STATUS

approved

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Last modified January 19 20:01 EST 2019. Contains 319309 sequences. (Running on oeis4.)