A088068 Squares sandwiched between two numbers divisible by squares.

49, 1681, 1849, 3249, 6724, 8649, 9801, 11449, 13689, 13924, 20449, 24649, 28224, 37249, 42849, 57121, 59049, 63001, 66049, 85849, 94249, 106929, 110224, 117649, 127449, 135424, 154449, 165649, 190969, 196249, 208849, 243049, 257049, 265225

Offset: 1

Author

Amarnath Murthy, Sep 22 2003

Keywords

• nonn

Comments

Sequence is infinite. k^2 is a member if k == 7 (mod 50), or k == -7 (mod 50).

Examples

			49 is a term as 48 and 50 are divisible by squares.
		

Crossrefs

Cf. A088069.

Programs

Mathematica

okQ[n_]:=Max[Transpose[FactorInteger[n]][[2]]]>1; Select[Range[600]^2,okQ[#-1]&&okQ[#+1]&]  (* Harvey P. Dale, Jan 26 2011 *)

Extensions

Corrected and extended by Ray Chandler, Sep 27 2003