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A107606
Perfect powers which have the form prime(n) + n for some n.
5
8, 16, 27, 32, 49, 529, 676, 1000, 1225, 1521, 1681, 1764, 2744, 3249, 4096, 5929, 9604, 10404, 10609, 11664, 12321, 19600, 24336, 25921, 26569, 27889, 33856, 34225, 34596, 46656, 51984, 68921, 71289, 72361, 91204, 100489, 101124, 104976
OFFSET
1,1
COMMENTS
Corresponding n's are in A107605.
FORMULA
A107606(n) = prime[A107605(n)] + A107605(n)
MATHEMATICA
f[n_] := Prime[n] + n; Select[f /@ Range[10^4], ! GCD @@ Last /@ FactorInteger[ # ] == 1 &] (* Ray Chandler, May 21 2005 *)
perfPQ[n_]:=GCD@@FactorInteger[n][[All, 2]]>1; Select[Table[Prime[n]+n, {n, 10000}], perfPQ] (* Harvey P. Dale, Jan 28 2023 *)
CROSSREFS
Cf. A001597 (perfect powers), A107605 (associated n), A107607, A107608.
Sequence in context: A090081 A059172 A360558 * A354561 A349306 A245713
KEYWORD
nonn
AUTHOR
Zak Seidov, May 17 2005
EXTENSIONS
Extended by Ray Chandler and Robert G. Wilson v, May 21 2005
STATUS
approved