A145050 - OEIS

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A145050

Primes p of the form 4k+1 for which s=26 is the least positive integer such that sp-(floor(sqrt(sp)))^2 is a square.

6569, 8117, 8689, 9221, 9281, 9829

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OFFSET

1,1

COMMENTS

For all primes of the form 4k+1 not exceeding 10000 the least integer s takes only values: 1, 2, 5, 10, 13, 17, 26. These values are the first numbers in A145017 (see our conjecture at A145047).

LINKS

Table of n, a(n) for n=1..6.

EXAMPLE

a(1)=6569 since p=6569 is the least prime of the form 4k+1 for which sp-(floor(sqrt(sp)))^2 is not a square for s=1..25, but 26p-(floor(sqrt(26p)))^2 is a square (for p=6569 it is 225).

CROSSREFS

Cf. A145016, A145017, A145022, A145023, A145043, A145047, A145048, A145049.

Sequence in context: A031579 A288884 A031759 * A319604 A256837 A216177

Adjacent sequences: A145047 A145048 A145049 * A145051 A145052 A145053

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Sep 30 2008, Oct 03 2008

STATUS

approved