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 A144111 Number of different pairs of primes p and q with p
 1, 2, 3, 4, 6, 7, 8, 10, 8, 11, 13, 11, 16, 14, 16, 15, 20, 18, 17, 21, 21, 23, 23, 22, 25, 27, 26, 25, 29, 28, 30, 30, 29, 33, 34, 34, 34, 35, 36, 40, 40, 39, 38, 42, 40, 45, 42, 45, 44, 47, 45, 50, 45, 51, 46, 47, 53, 55, 54, 56, 52, 55, 54, 53, 61, 55, 58, 59, 59, 62, 63, 64 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The sequence is infinite LINKS EXAMPLE 6*2=12 5+7=12, 2=r(1) so a(1)=1 6*3=18 5+13=18, 7+11=18, 3=r(2) so a(2)=2 6*5=30 7+23=30, 11+19=30, 13+17=30, 5=r(3) so a(3)=3 CROSSREFS Sequence in context: A209643 A039123 A131618 * A039257 A039198 A249299 Adjacent sequences:  A144108 A144109 A144110 * A144112 A144113 A144114 KEYWORD nonn AUTHOR Pierre CAMI, Sep 11 2008 STATUS approved

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Last modified September 23 04:54 EDT 2020. Contains 337295 sequences. (Running on oeis4.)