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A064915 Positive integers n that are not of the form p + q * a^2, where p and q are primes and a is the smallest prime not dividing n. 1
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 22, 24, 26, 28, 30, 36, 42, 48, 54, 60, 66, 72, 77, 84, 90, 96, 102, 108, 114, 120, 126, 174, 180, 210, 240, 270, 300, 330, 420, 630, 840, 1050, 1260 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

There are no other terms up to 10^7. Conjecture: There are no more terms in the sequence.

MATHEMATICA

rep[ n_ ] := Module[ {a, q}, For[ a=2, GCD[ n, a ]!=1, a++, Null ]; For[ q=2, q a^2<n, q++, If[ PrimeQ[ q ]&&PrimeQ[ n-q a^2 ], Return[ True ] ] ]; False ]; Select[ Range[ 1, 10000 ], !rep[ # ]& ]

CROSSREFS

Cf. A064653.

Sequence in context: A130232 A103969 A030141 * A180648 A175740 A120003

Adjacent sequences:  A064912 A064913 A064914 * A064916 A064917 A064918

KEYWORD

nonn

AUTHOR

Dean Hickerson (dean.hickerson(AT)yahoo.com), Oct 13 2001

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Last modified February 17 04:56 EST 2012. Contains 205985 sequences.