id:A108154 - OEIS Search Results

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a(n) = n^2 - n + 1 if prime else 0.

+0
1

0, 3, 7, 13, 0, 31, 43, 0, 73, 0, 0, 0, 157, 0, 211, 241, 0, 307, 0, 0, 421, 463, 0, 0, 601, 0, 0, 757, 0, 0, 0, 0, 0, 1123, 0, 0, 0, 0, 1483, 0, 0, 1723, 0, 0, 0, 0, 0, 0, 0, 0, 2551, 0, 0, 0, 2971, 0, 0, 3307, 0, 3541, 0, 0, 3907, 0, 0, 0, 4423, 0, 0, 4831, 0, 5113, 0, 0, 0, 5701, 0 (list; graph; listen)

	OFFSET	`1,2`
	EXAMPLE	`1^2-1+1=1 not prime so a(1)=0` `2^2-2+1=3 prime so a(2)=3` `3^3-3+1=7 prime so a(3)=7`
	MATHEMATICA	`f[n_] := Block[{p = n^2 - n + 1}, If[ PrimeQ[p], p, 0]]; Table[ f[n], {n, 77}] (from Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 07 2005)`
	CROSSREFS	`Cf. A002383, A002384.` `Sequence in context: A167490 A081533 A096856 this_sequence A010260 A128156 A108768` `Adjacent sequences: A108151 A108152 A108153 this_sequence A108155 A108156 A108157`
	KEYWORD	`easy,nonn`
	AUTHOR	`Pierre CAMI (pierrecami(AT)tele2.fr), Jun 06 2005`
	EXTENSIONS	`More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 07 2005`

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Last modified November 23 10:40 EST 2009. Contains 167421 sequences.

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