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A075076 Integers pertaining to A075075: a(n) = b(n-1)*b(n+1)/b(n) where b(n) is the n-th term of A075075. 3
2, 3, 2, 10, 6, 4, 15, 6, 20, 12, 12, 30, 12, 28, 6, 33, 14, 7, 44, 13, 14, 34, 26, 15, 51, 18, 55, 36, 24, 55, 20, 56, 30, 30, 56, 39, 36, 68, 52, 42, 85, 40, 77, 60, 45, 77, 42, 99, 56, 56, 99, 72, 80, 54, 57, 30, 46, 38, 29, 23, 62, 58, 37, 31, 82, 74, 38, 123, 38, 86, 114, 39 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

This is not a permutation of the natural numbers since a(4)=a(2), a(9)=a(6), a(12)=a(11) etc. [From Hagen von Eitzen, May 16 2009]

LINKS

Alois P. Heinz, Table of n, a(n) for n = 2..10000

MAPLE

c:= proc() false end:

b:= proc(n) option remember; local k, m;

       if n<3 then k:=n

     else m:= denom(b(n-2) /b(n-1));

          for k from m by m while c(k) do od

       fi;

       c(k):= true; k

    end:

a:= n-> b(n-1)*b(n+1)/b(n):

seq(a(n), n=2..100);  # Alois P. Heinz, Jul 18 2012

MATHEMATICA

Clear[b, c]; c[_] = False; b[n_] := b[n] = Module[{k, m}, If[n<3, k = n, m = Denominator[b[n-2]/b[n-1]]; For[k = m, c[k], k = k+m]]; c[k] = True; k]; a[n_] := b[n-1]*b[n+1]/b[n]; Table[a[n], {n, 2, 100}] (* Jean-Fran├žois Alcover, Jun 10 2015, after Alois P. Heinz *)

CROSSREFS

Cf. A075075.

Sequence in context: A126286 A126288 A205393 * A333129 A078828 A247170

Adjacent sequences:  A075073 A075074 A075075 * A075077 A075078 A075079

KEYWORD

nonn,look

AUTHOR

Amarnath Murthy, Sep 09 2002

EXTENSIONS

More terms from Sascha Kurz, Feb 03 2003

STATUS

approved

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Last modified April 11 00:03 EDT 2021. Contains 342877 sequences. (Running on oeis4.)