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A087818 Consider numbers x = 4n + 1 which are of the form x = y^2 + z^2 with y <= z; sequence gives smallest value of y. 1
1, 1, 3, 2, 1, 3, 2, 1, 4, 3, 7, 2, 5, 1, 3, 9, 2, 5, 4, 1, 3, 7, 6, 11, 2, 4, 1, 7, 3, 6, 5, 2, 9, 4, 7, 1, 3, 5, 9, 2, 8, 4, 7, 1, 6, 3, 10, 9, 5, 8, 2, 4, 12, 11, 1, 3, 9, 5, 8, 19, 2, 12, 7, 4, 10, 6, 1, 9, 3, 14, 5, 12, 21, 2, 7, 4, 10, 6, 9, 1, 3, 8, 5, 11, 23, 2, 10, 4, 15, 14, 6, 13, 1, 3, 8, 5, 11 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..97.

EXAMPLE

x=45, y=3, z=6. 45-9 = 36 = 6^2

PROG

(PARI) fourkp1(n) = { forstep(x=1, n, 4, for(y=1, floor(sqrt(x)), z=x-y^2; if(issquare(z), print1(y" "); break; ) ) ) }

CROSSREFS

Cf. A087819.

Sequence in context: A130784 A138034 A229216 * A112746 A107460 A152975

Adjacent sequences:  A087815 A087816 A087817 * A087819 A087820 A087821

KEYWORD

nonn

AUTHOR

Cino Hilliard, Oct 06 2003

STATUS

approved

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Last modified October 21 19:58 EDT 2019. Contains 328315 sequences. (Running on oeis4.)