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 A155764 Records in A047160. 4
 0, 1, 3, 9, 15, 18, 21, 27, 33, 39, 42, 45, 48, 75, 87, 93, 117, 120, 135, 138, 168, 183, 210, 228, 300, 333, 369, 393, 453, 525, 621, 720, 810, 846, 1086, 1281, 1305, 1515, 1590, 1617, 1722, 1794, 1833, 1851, 2010, 2064, 2085, 2112, 2217, 2352, 2754, 2784 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Other than a(2)=1, every known term is a multiple of three. Equivalently, assuming A155765(n) - a(n) != 3, no term of A155765 is a multiple of three. - Jason Kimberley, Oct 16 and 24 2012 Conjecture 1: a(n) < 0.138*log(A155765(n))^3.6 for n > 4. Conjecture 2: If Conjecture 1 and Goldbach's conjecture hold, for any integer m > 22, there exist at least one pairs of primes m-d and m+d such that d < 0.138*log(m)^3.6. - Ya-Ping Lu, Nov 27 2020 LINKS Gilmar Rodriguez Pierluissi, Table of n, a(n) for n = 1..64 (terms 1..61 from T. D. Noe) OEIS (Plot 2), Plot of (log(A155765(n)), log(A155764(n))) - Jason Kimberley, Oct 24 2012 FORMULA a(n) = A047160(A155765(n)). - Jason Kimberley, Sep 01 2011 MATHEMATICA mgppp[n_?EvenQ]/; n>3:=Block[{m=PrimePi[n/2], p}, While[!PrimeQ[n-(p=Prime[m])], m--]; p]; dist[n_?EvenQ]:=Module[{d}, {m=n/2, d=(m-mgppp[n])}; d] For[n=4; a=-1, True, n+=2, b=dist[n]; If[b>a, Print[b]; a=b]] (* Gilmar Rodriguez Pierluissi, Aug 27 2018 *) PROG (Python) from sympy import isprime a_rec = -1 m = 2 while 1: a = 0 while a < m - 1: if isprime(m-a) == 1 and isprime(m+a) == 1: if a > a_rec: print(a) a_rec = a break a += 1 m += 1 # Ya-Ping Lu, Nov 27 2020 CROSSREFS Cf. A155765 (where records occur in A047160). Sequence in context: A310328 A043381 A100331 * A259754 A277569 A310329 Adjacent sequences: A155761 A155762 A155763 * A155765 A155766 A155767 KEYWORD nonn AUTHOR T. D. Noe, Jan 27 2009 STATUS approved

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Last modified October 1 14:39 EDT 2023. Contains 365826 sequences. (Running on oeis4.)