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A330650 Terms of A330606 which are not squares or powers of 2. 1
1250, 4802, 31250, 57122, 167042, 235298, 260642, 320000, 559682, 941192, 1229312, 1414562, 3001250, 3543122, 3748322, 5120000, 6837602, 8000000, 9653618, 9759362, 14172488, 14623232, 15059072, 15780962, 19531250, 19668992, 24234722, 35701250, 38614472, 40302242 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..655 (terms < 10^13, first 155 terms from Amiram Eldar and Robert G. Wilson v)

MATHEMATICA

fQ[n_] := CoprimeQ[n*DivisorSigma[0, n], DivisorSigma[1, n]] && !IntegerQ@ Sqrt@ n && !IntegerQ@ Log2@ n; Select[Range[10^6], fQ@# &]

PROG

(MAGMA) [k:k in [1..10000000]|Gcd(k*NumberOfDivisors(k), DivisorSigma(1, k)) eq 1 and (not IsSquare(k)) and (not IsIntegral(Log(2, k)))]; // Marius A. Burtea, Dec 23 2019

CROSSREFS

Cf. A330606.

Sequence in context: A120376 A231805 A122272 * A195810 A184610 A106322

Adjacent sequences:  A330647 A330648 A330649 * A330651 A330652 A330653

KEYWORD

nonn

AUTHOR

Amiram Eldar and Robert G. Wilson v, Dec 22 2019

STATUS

approved

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Last modified July 29 17:20 EDT 2021. Contains 346346 sequences. (Running on oeis4.)