OFFSET
1,1
MATHEMATICA
PrimeFactors[n_Integer] := Flatten[ Table[ # [[1]], {1}] & /@ FactorInteger[n]]; a[1] = 1; a[n_] := a[n] = (Plus @@ (a[ # ] & /@ Complement[ Range[ PrimePi[n]], PrimePi[ PrimeFactors[n]]])); Take[ Complement[ Range[150], Union[ Table[ a[n], {n, 150}]]], 61]
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, May 04 2004
STATUS
approved