OFFSET
1,2
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..10000
MATHEMATICA
lst = {}; r[n_] := (len = Length@lst; lst = Flatten@ Join[lst, Select[First /@ FactorInteger[Prime@n - 1], ! MemberQ[lst, # ] &]]; If[l < Length@lst, 1, 0]); Do[ r[n], {n, 260}]; Table[Position[lst, Prime[n]], {n, 71}] // Flatten
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Nov 29 2005
STATUS
approved