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 A280134 Number of primes of the form 4(n - k - 1) + 3 where 0 <= k and prime of the form 4k + 3 <= n. 1
 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 2, 2, 1, 1, 1, 2, 2, 3, 2, 3, 3, 2, 1, 2, 2, 2, 2, 1, 1, 2, 2, 3, 3, 2, 2, 3, 2, 3, 3, 1, 4, 3, 1, 4, 3, 2, 3, 4, 3, 2, 5, 3, 2, 4, 2, 4, 4, 3, 4, 4, 3, 3, 5, 2, 2, 6, 4, 2, 5, 4, 3, 6, 3, 2, 3, 4, 4, 5, 3, 2, 6, 4, 3, 5, 1, 5, 6, 2, 3, 4, 4, 3, 6, 3, 4, 8, 3, 3, 4, 3, 3, 5, 2, 2, 6, 4, 3, 6, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,12 COMMENTS (1) Conjecture: a(n) > 0 for n >= 11. (2) Conjecture: A278287(n) > 0 for n >= 11. Conjecture (1) and conjecture (2) are first and second parts of Goldbach-like conjecture in A001031. LINKS EXAMPLE a(12) = 2 because 4*(12-0-1)+3 = 47 and 4*0+3 = 3 are primes where 3 < 12 and 4*(12-1-1)+3 = 43 and 4*1+3 = 7 are primes where 7 < 12. CROSSREFS Cf. A001031, A002144, A278287. Sequence in context: A237112 A238013 A303940 * A143488 A201159 A047070 Adjacent sequences:  A280131 A280132 A280133 * A280135 A280136 A280137 KEYWORD nonn AUTHOR Juri-Stepan Gerasimov, Dec 26 2016 STATUS approved

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Last modified June 5 03:12 EDT 2020. Contains 334828 sequences. (Running on oeis4.)