0,2
Carlos Rivera, The Prime Puzzles & Problems Connection: Puzzle 172.
a(7)=15: there are 7 primes (2, 3, 5, 7, 11, 13, 17) and 8 ones.
Sequence in context: A117952 A162999 A064509 this_sequence A120367 A072831 A072388
Adjacent sequences: A096218 A096219 A096220 this_sequence A096222 A096223 A096224
nonn
Ray G. Opao (1260(AT)email.com), Jul 29 2004
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