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A094599 Numbers n such that the Lebesgue-Nagell equation x^2 + n = y^k, with k > 2, has an integer solution. 3
1, 2, 4, 7, 8, 11, 12, 13, 15, 16, 17, 18, 19, 20, 23, 25, 26, 27, 28, 31, 32, 35, 39, 40, 44, 45, 47, 48, 49, 53, 54, 55, 56, 60, 61, 63, 64, 65, 67, 71, 72, 74, 76, 77, 79, 80, 81, 83, 87, 89, 92, 95, 96, 97, 99, 100 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..56.

MATHEMATICA

lst=Table[cnt=0; Do[x=Sqrt[y^k-n]; If[IntegerQ[x], cnt++ ], {k, 3, 20}, {y, 600}]; cnt, {n, 2, 100}]; Complement[Range[100], Flatten[Position[lst, 0]]+1]

CROSSREFS

Cf. A094596, A094597, A094598.

Sequence in context: A045601 A167051 A151661 * A050082 A209864 A182654

Adjacent sequences:  A094596 A094597 A094598 * A094600 A094601 A094602

KEYWORD

hard,nonn

AUTHOR

T. D. Noe, May 13 2004

STATUS

approved

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Last modified October 25 11:10 EDT 2021. Contains 348240 sequences. (Running on oeis4.)