A081649 - OEIS

A081649

Integers congruent to 0, 1, 4, 9, 16, 25, 36, 49, 64 or 81 (mod 100) which are not squares.

101, 104, 109, 116, 125, 136, 149, 164, 181, 200, 201, 204, 209, 216, 236, 249, 264, 281, 300, 301, 304, 309, 316, 325, 336, 349, 364, 381, 401, 404, 409, 416, 425, 436, 449, 464, 481, 500, 501, 504, 509, 516, 525, 536, 549, 564, 581, 600, 601, 604, 609

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

REFERENCES

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

LINKS

Table of n, a(n) for n=1..51.

MATHEMATICA

Select[ Range[615], (Mod[ #, 100] == 0 || Mod[ #, 100] == 1 || Mod[ #, 100] == 4 || Mod[ #, 100] == 9 || Mod[ #, 100] == 16 || Mod[ #, 100] == 25 || Mod[ #, 100] == 36 || Mod[ #, 100] == 49 || Mod[ #, 100] == 64 || Mod[ #, 100] == 81) && !IntegerQ[ Sqrt[ # ]] & ]

icQ[n_]:=!IntegerQ[Sqrt[n]]&&MemberQ[Range[0, 9]^2, Mod[n, 100]]; Select[ Range[ 700], icQ] (* Harvey P. Dale, Jan 08 2019 *)

CROSSREFS

Sequence in context: A060400 A128717 A111348 * A344802 A126118 A118773

Adjacent sequences: A081646 A081647 A081648 * A081650 A081651 A081652

KEYWORD

easy,nonn

AUTHOR

Robert G. Wilson v, Mar 26 2003

STATUS

approved