OFFSET
1,6
COMMENTS
LINKS
T. D. Noe, Table of n, a(n) for n = 1..10000
FORMULA
G.f.: (Sum_{k>=1} x^prime(k))*(Sum_{k = i^j, i>=1, j>=2} x^k). - Ilya Gutkovskiy, Feb 18 2017
EXAMPLE
a(1) = a(2) = a(5) = a(1549) = a(1771561) = 0, see A119748.
MATHEMATICA
nn = 100; pwrs = Union[{1}, Flatten[Table[Range[2, Floor[nn^(1/ex)]]^ex, {ex, 2, Floor[Log[2, nn]]}]]]; pp = Prime[Range[PrimePi[nn]]]; t = Table[0, {nn}]; Do[ t[[i[[1]]]] = i[[2]], {i, Tally[Sort[Select[Flatten[Outer[Plus, pwrs, pp]], # <= nn &]]]}]; t (* T. D. Noe, Sep 29 2011 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Philippe Deléham, Sep 29 2011
EXTENSIONS
Edited by Franklin T. Adams-Watters, Sep 29 2011
STATUS
approved