A056898 - OEIS

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A056898

a(n) = smallest number m such that m^2+n is prime.

1, 0, 0, 1, 0, 1, 0, 3, 2, 1, 0, 1, 0, 3, 2, 1, 0, 1, 0, 3, 4, 1, 0, 7, 2, 9, 2, 1, 0, 1, 0, 3, 2, 3, 6, 1, 0, 3, 2, 1, 0, 1, 0, 3, 4, 1, 0, 5, 2, 3, 4, 1, 0, 5, 2, 9, 2, 1, 0, 1, 0, 3, 2, 3, 6, 1, 0, 9, 2, 1, 0, 1, 0, 3, 2, 5, 6, 1, 0, 3, 4, 1, 0, 5, 2, 9, 4, 1, 0, 7, 4, 3, 2, 3, 6, 1, 0, 3, 2 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,8`
	FORMULA	`a(n) = sqrt(A056896(n)-n) = sqrt(A056897(n)). For p a prime: a(p) = 0 (and a(p-1) = 1 if p<>3).`
	EXAMPLE	`a(8) = 3 since 3^2+8 = 17 which is prime`
	CROSSREFS	`Cf. A000040, A002496, A056892-A056898.` `Sequence in context: A021761 A171839 A071960 * A204176 A062160 A194703` `Adjacent sequences: A056895 A056896 A056897 * A056899 A056900 A056901`
	KEYWORD	`nonn`
	AUTHOR	`Henry Bottomley (se16(AT)btinternet.com), Jul 05 2000`

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Last modified February 14 06:53 EST 2012. Contains 205577 sequences.