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A025020 Least non-residue mod n is 2. 0
3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 15, 16, 18, 19, 20, 21, 22, 24, 25, 26, 27, 28, 29, 30, 32, 33, 35, 36, 37, 38, 39, 40, 42, 43, 44, 45, 48, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 63, 64, 65, 66, 67, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 83, 84, 85, 86, 87, 88, 90, 91, 92 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

Eric Weisstein's World of Mathematics, Quadratic Nonresidue

PROG

(PARI) isA025020(n)={local(r); r=1; for(m=1, n-1, if(m^2%n==2, r=0)); r} [From Michael B. Porter (michael_b_porter(AT)yahoo.com), Apr 16 2010]

CROSSREFS

Sequence in context: A003619 A183294 A039234 * A028974 A184427 A001965

Adjacent sequences:  A025017 A025018 A025019 * A025021 A025022 A025023

KEYWORD

nonn

AUTHOR

David W. Wilson (davidwwilson(AT)comcast.net)

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Last modified February 14 08:24 EST 2012. Contains 205614 sequences.