A062610 - OEIS

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A062610

Number of ways of writing n = c1+c2 with c1 and c2 nonprimes [=1 or composite].

0, 1, 0, 0, 1, 0, 1, 1, 1, 2, 1, 2, 2, 2, 2, 4, 2, 4, 3, 4, 3, 5, 3, 6, 4, 6, 4, 7, 5, 8, 6, 7, 6, 9, 6, 11, 7, 8, 8, 11, 8, 12, 9, 11, 9, 12, 9, 14, 10, 14, 10, 14, 11, 16, 12, 15, 12, 16, 13, 19, 14, 15, 14, 19, 14, 21, 15, 17, 16, 21, 16, 22, 17, 20, 17, 22, 17, 25, 18, 22, 19, 23, 19 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,10`
	LINKS	`Index entries for sequences related to Goldbach conjecture` `Donovan Johnson, Table of n, a(n) for n = 1..10000`
	EXAMPLE	`n = 22 has Floor[n/2] = 11 partitions of form n = a+b; 3 partitions are of prime+prime [3+19 = 5+17 = 11+11], 3 partitions are of prime+nonprime [2+20 = 7+15 = 13+9], 5 partitions are of nonprime+nonprime [1+21 = 4+18 = 6+16 = 8+14 = 10+12]. So a(22) = 5.`
	CROSSREFS	`Cf. A061358, A014092, A062602.` `Sequence in context: A117173 A103858 A010554 * A025801 A060548 A140426` `Adjacent sequences: A062607 A062608 A062609 * A062611 A062612 A062613`
	KEYWORD	`nonn`
	AUTHOR	`Labos E. (labos(AT)ana.sote.hu), Jul 04 2001`

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Last modified February 14 23:53 EST 2012. Contains 205689 sequences.