cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A095390 Least inverse of A095389.

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%I A095390 #6 Oct 15 2013 22:32:25
%S A095390 64,28,11,14,5,3,2,1,968
%N A095390 Least inverse of A095389.
%C A095390 It is believed (or proved) that values at n > 8 indices do not occur, except once, at the beginning when 13 lesser twins in 210.0+R range, where R is the reduced residues modulo 210.
%F A095390 a(n) = min{x: A095389(x) = n}
%e A095390 a(13) = 0 because A095389(0) = 13.
%e A095390 a(1) = 28 means that in reduced residue system 210.28+R exactly 1 lesser-twin-prime arises; see A095389.
%e A095390 a(8) = 968 means that at surprisingly high density of twin primes [8 cases] occur in range of {210.968+r, 210.968+r+2}, as follows: {203309, 203321, 203339, 203351, 203381, 203417, 203429, 203459}.
%t A095390 {k=0, ta=Table[0, {100000}]}; Do[{m=0};Do[s=210k+r; s1=210k+r+2; If[PrimeQ[s]&&PrimeQ[s+2], m=m+1], {r, 1, 210}];ta[[k]]=m, {k, 1, 100000}]; Table[Min[Flatten[Position[ta, j]]], {j, 0, 15}]
%Y A095390 Cf. A095389, A078859.
%K A095390 fini,nonn
%O A095390 0,1
%A A095390 _Labos Elemer_, Jun 16 2004
%E A095390 Edited by _Charles R Greathouse IV_, Oct 27 2010