A144854 Values of n such that the expression sqrt(4!*(n+1) + 1) yields a perfect power.

25, 99, 609, 650, 1189, 3479, 4901, 5429, 11659, 16275, 29469, 38479, 62525, 73814, 78089, 117739, 142449, 201116, 203319, 240199, 328769, 381275, 406900, 504889, 576909, 743775, 839629, 1005731, 1058819, 1183259, 1464709, 1622919, 1960244

Offset

1,1

Links

Table of n, a(n) for n=1..33.

Example

25 is in the sequence since sqrt(4!*(25+1) + 1) = 25 = 5^2;
99 is in the sequence since sqrt(4!*(99+1) + 1) = 49 = 7^2. - Jon E. Schoenfield, Aug 01 2015

Mathematica

lst = {}; Do[a = Sqrt[4! (n + 1) + 1]; If[IntegerQ@ a && GCD @@ Last /@ FactorInteger@a > 1, AppendTo[lst, n]], {n, 0, 1977428}]; lst (* Robert G. Wilson v, Sep 24 2008 *)

Crossrefs

Subset of A144065.

Sequence in context: A099771 A266818 A158547 * A237202 A353152 A335717

Adjacent sequences: A144851 A144852 A144853 * A144855 A144856 A144857

Keyword

nonn

Author

Alexander R. Povolotsky, Sep 22 2008

Extensions

More terms from Robert G. Wilson v, Sep 24 2008

Status

approved