A095390 Least inverse of A095389.

64, 28, 11, 14, 5, 3, 2, 1, 968

Offset

0,1

Comments

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.

Links

Table of n, a(n) for n=0..8.

Formula

a(n) = min{x: A095389(x) = n}

Example

a(13) = 0 because A095389(0) = 13.
a(1) = 28 means that in reduced residue system 210.28+R exactly 1 lesser-twin-prime arises; see A095389.
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}.

Mathematica

{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}]

Crossrefs

Cf. A095389, A078859.

Sequence in context: A275469 A178542 A066539 * A033384 A073327 A169639

Adjacent sequences: A095387 A095388 A095389 * A095391 A095392 A095393

Keyword

fini,nonn

Author

Labos Elemer, Jun 16 2004

Extensions

Edited by Charles R Greathouse IV, Oct 27 2010

Status

approved