A054019 - OEIS

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A054019

Square roots of A054018.

3, 1, 4, 3, 5, 4, 5, 7, 4, 1, 8, 11, 6, 9, 8, 13, 8, 6, 10, 15, 8, 6, 11, 6, 13, 7, 19, 15, 1, 12, 21, 21, 12, 16, 20, 14, 8, 21, 1, 12, 19, 8, 20, 21, 27, 8, 14, 12, 27, 10, 29, 27, 5, 20, 16, 35, 10, 27, 35, 31, 30, 29, 3, 12, 28, 5, 1, 35, 26, 10, 20, 37, 12, 33, 18, 43, 43, 45, 22

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OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

MATHEMATICA

chowla[n_] := DivisorSigma[1, n] - n - 1; aQ[n_] := (c = chowla[n]) > 0 && IntegerQ@Sqrt@Mod[c, n]; Sqrt @ Mod[chowla[#], #] & /@ Select[Range[1000], aQ] (* Amiram Eldar, Aug 28 2019 *)

CROSSREFS

Cf. A048050, A054013, A054017, A054018.

Sequence in context: A102595 A113415 A332801 * A333477 A230877 A326041

Adjacent sequences: A054016 A054017 A054018 * A054020 A054021 A054022

KEYWORD

nonn

AUTHOR

Asher Auel, Jan 19 2000

STATUS

approved