id:A107987 - OEIS Search Results

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Odd composite numbers of the form p+2 where p is prime.

+0
1

9, 15, 21, 25, 33, 39, 45, 49, 55, 63, 69, 75, 81, 85, 91, 99, 105, 111, 115, 129, 133, 141, 153, 159, 165, 169, 175, 183, 195, 201, 213, 225, 231, 235, 243, 253, 259, 265, 273, 279, 285, 295, 309, 315, 319, 333, 339, 351, 355, 361, 369, 375, 381, 385, 391, 399 (list; graph; listen)

	OFFSET	`1,1`
	PROGRAM	`(PARI) sum2pr(n) = \Composite numbers of form p+2. { c=0; cp=0; forprime(x=2, n, cp++; y=x+2; if(isprime(y)==0, c++; print1(y", ") ) ); print(); print(c/cp+.) }`
	CROSSREFS	`Cf. A067774.` `Adjacent sequences: A107984 A107985 A107986 this_sequence A107988 A107989 A107990` `Sequence in context: A046315 A046372 A025045 this_sequence A031879 A063139 A097636`
	KEYWORD	`easy,nonn`
	AUTHOR	`Cino Hilliard (hillcino368(AT)gmail.com), Jun 13 2005`

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Last modified May 11 10:28 EDT 2008. Contains 139662 sequences.

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