A081646 Integers congruent to 0, 1, 4, 9, 16, 25 or 36 (mod 49) which are not squares.

50, 53, 58, 65, 74, 85, 98, 99, 102, 107, 114, 123, 134, 147, 148, 151, 156, 163, 172, 183, 197, 200, 205, 212, 221, 232, 245, 246, 249, 254, 261, 270, 281, 294, 295, 298, 303, 310, 319, 330, 343, 344, 347, 352, 359, 368, 379, 392, 393, 396, 401, 408, 417

Offset: 1

Author

Robert G. Wilson v, Mar 26 2003

Keywords

• easy
• nonn

References

• Mark A. Herkommer, Number Theory, A Programmer's Guide, McGraw-Hill, New York, 1999, page 315.

Programs

Mathematica

Select[ Range[427], (Mod[ #, 49] == 0 || Mod[ #, 49] == 1 || Mod[ #, 49] == 4 || Mod[ #, 49] == 9 || Mod[ #, 49] == 16 || Mod[ #, 49] == 25 || Mod[ #, 49] == 36) && !IntegerQ[ Sqrt[ # ]] & ]
Select[Range[500],MemberQ[{0,1,4,9,16,25,36},Mod[#,49]]&&!IntegerQ[Sqrt[#]]&] (* Harvey P. Dale, Sep 10 2024 *)