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 A071701 Number of twin prime pairs <= n of form (4*k+1,4*k+3), k>0. 1
 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,17 COMMENTS As for A071538 the convention is followed that a twin prime pair is <= n if its smaller member is <= n. LINKS EXAMPLE a(30)=3, since (29,31) is included along with (5,7) and (17,19). CROSSREFS a(n) = A071538(n) - A071702(n), cf. A071695, A071696. Sequence in context: A179076 A095861 A111855 * A342696 A064459 A279758 Adjacent sequences:  A071698 A071699 A071700 * A071702 A071703 A071704 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jun 04 2002 STATUS approved

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Last modified January 19 02:30 EST 2022. Contains 350464 sequences. (Running on oeis4.)