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A020481 Least p with p, q both prime, p+q = 2n. 12
2, 3, 3, 3, 5, 3, 3, 5, 3, 3, 5, 3, 5, 7, 3, 3, 5, 7, 3, 5, 3, 3, 5, 3, 5, 7, 3, 5, 7, 3, 3, 5, 7, 3, 5, 3, 3, 5, 7, 3, 5, 3, 5, 7, 3, 5, 7, 19, 3, 5, 3, 3, 5, 3, 3, 5, 3, 5, 7, 13, 11, 13, 19, 3, 5, 3, 5, 7, 3, 3, 5, 7, 11, 11, 3, 3, 5, 7, 3, 5, 7, 3, 5, 3, 5, 7, 3, 5, 7, 3, 3, 5, 7, 11, 11, 3, 3, 5, 3, 3, 5, 7 (list; graph; refs; listen; history; internal format)
OFFSET

2,1

COMMENTS

Essentially the same as A002373, which does not have the a(2) term. - T. D. Noe (noe(AT)sspectra.com), Sep 24 2007

LINKS

H. J. Smith, Table of n, a(n) for n = 2..20000

PROG

(PARI) A020481(n) = {local(np); np=1; while(!isprime(2*n-prime(np)), np++); prime(np)} [From Michael Porter (michael_b_porter(AT)yahoo.com), Dec 11 2009]

CROSSREFS

Sequence in context: A064338 A197592 A103359 * A066660 A057957 A076559

Adjacent sequences:  A020478 A020479 A020480 * A020482 A020483 A020484

KEYWORD

nonn

AUTHOR

David W. Wilson (davidwwilson(AT)comcast.net)

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Last modified February 14 16:57 EST 2012. Contains 205635 sequences.