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A081649 Integers congruent to 0, 1, 4, 9, 16, 25, 36, 49, 64 or 81 (mod 100) which are not squares. 1
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 * A126118 A118773 A092628

Adjacent sequences:  A081646 A081647 A081648 * A081650 A081651 A081652

KEYWORD

easy,nonn

AUTHOR

Robert G. Wilson v, Mar 26 2003

STATUS

approved

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Last modified September 26 16:43 EDT 2020. Contains 337374 sequences. (Running on oeis4.)