OFFSET
1,2
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
MATHEMATICA
f[ n_Integer ] := Block[ {k = n + PrimePi[ n ] + 1}, While[ k - PrimePi[ k ] - 1 != n, k++ ]; k ]; s = 0; Do[ s = s + f[ n ]; If[ ! PrimeQ[ s ], Print[ n ] ], {n, 1, 100} ]
With[{comps=Rest[Select[Range[150], !PrimeQ[#]&]]}, Rest[Flatten[ Position[ Accumulate[ comps], _?(!PrimeQ[#]&)]]]] (* Harvey P. Dale, Oct 16 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from David W. Wilson
STATUS
approved