A028803 - OEIS

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A028803

Nonsquares mod 90.

2, 3, 5, 6, 7, 8, 11, 12, 13, 14, 15, 17, 18, 20, 21, 22, 23, 24, 26, 27, 28, 29, 30, 32, 33, 35, 37, 38, 39, 41, 42, 43, 44, 47, 48, 50, 51, 52, 53, 56, 57, 58, 59, 60, 62, 63, 65, 66, 67, 68, 69, 71, 72, 73, 74, 75, 77, 78, 80, 82, 83, 84, 86, 87, 88, 89 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,1`
	LINKS	`Table of n, a(n) for n=1..66.`
	MATHEMATICA	`Complement[Range[0, 89], PowerMod[Range[90], 2, 90]] (* Alonso del Arte, Jan 03 2020 *)`
	PROG	`(Scala) (0 to 89).diff((1 to 90).map(n => n * n % 90)) // Alonso del Arte, Jan 03 2020`
	CROSSREFS	`Cf. A010451.` `Sequence in context: A219255 A025501 A028758 * A050942 A096600 A122686` `Adjacent sequences: A028800 A028801 A028802 * A028804 A028805 A028806`
	KEYWORD	`nonn,fini,full,easy`
	AUTHOR	`N. J. A. Sloane`
	STATUS	`approved`

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Last modified January 15 11:50 EST 2021. Contains 340187 sequences. (Running on oeis4.)