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A258613 Numbers m that are coprime to the largest square <= m, cf. A048760. 3
1, 2, 3, 5, 7, 10, 11, 13, 14, 17, 19, 21, 23, 26, 27, 28, 29, 31, 32, 33, 34, 37, 41, 43, 47, 50, 51, 52, 53, 54, 55, 57, 58, 59, 60, 61, 62, 65, 67, 69, 71, 73, 75, 77, 79, 82, 83, 85, 86, 88, 89, 91, 92, 94, 95, 97, 98, 101, 103, 107, 109, 111, 113, 117 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A074695(a(n)) = 1.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

EXAMPLE

a(8) = 13: GCD(13,A048760(13)) = GCD(13,9) = 1;

a(9) = 14: GCD(14,A048760(14)) = GCD(14,9) = 1;

but GCD(15,A048760(15)) = GCD(15,9) = 3 > 1, therefore 15 isn't a term.

MATHEMATICA

Select[Range[200], CoprimeQ[#, Floor[Sqrt[#]]^2]&] (* Harvey P. Dale, Jun 25 2017 *)

PROG

(Haskell)

a258613 n = a258613_list !! (n-1)

a258613_list = filter ((== 1) . a074695) [1..]

(PARI) isok(n) = gcd(n, sqrtint(n)^2) == 1; \\ Michel Marcus, Jun 06 2015

CROSSREFS

Cf. A074695, A048760, A258614 (complement).

Sequence in context: A325405 A118241 A325160 * A325460 A002269 A327445

Adjacent sequences:  A258610 A258611 A258612 * A258614 A258615 A258616

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jun 05 2015

STATUS

approved

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Last modified January 20 00:08 EST 2022. Contains 350467 sequences. (Running on oeis4.)