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A100867 Smallest positive integer k such that A000037(n) is not a quadratic residue modulo k. 1
3, 4, 3, 4, 4, 3, 4, 3, 5, 5, 3, 4, 3, 4, 4, 3, 8, 4, 3, 7, 3, 4, 5, 3, 4, 4, 3, 5, 4, 3, 5, 3, 4, 7, 3, 4, 4, 3, 7, 4, 3, 5, 3, 4, 5, 3, 4, 4, 3, 5, 4, 3, 9, 7, 3, 4, 3, 4, 4, 3, 7, 4, 3, 5, 5, 3, 4, 7, 3, 4, 4, 3, 4, 3, 9, 8, 3, 4, 5, 3, 4, 4, 3, 5, 4, 3, 7, 5, 3, 4, 3, 4, 4, 3, 9, 4, 3, 5, 8, 3, 4, 5, 3, 4, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The nonzero terms of A139401.

LINKS

Table of n, a(n) for n=1..105.

FORMULA

a(n) = A139401(A000037(n)).

EXAMPLE

a(1) = 3 because the first nonsquare positive integer is 2 and 2 is not a quadratic residue modulo 3.

CROSSREFS

Sequence in context: A046536 A052384 A276867 * A220196 A128200 A258168

Adjacent sequences:  A100864 A100865 A100866 * A100868 A100869 A100870

KEYWORD

nonn

AUTHOR

Guilherme de Queiroz Hobbs (guilhermehobbs(AT)uol.com.br), Jan 08 2005

EXTENSIONS

Corrected and extended by David Wasserman, Mar 04 2008

Edited by Max Alekseyev, May 11 2010

STATUS

approved

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Last modified December 8 06:53 EST 2021. Contains 349590 sequences. (Running on oeis4.)