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A242077
Numbers k such that no final group of decimal digits of k^2 less than the total forms a square.
2
4, 5, 6, 14, 16, 24, 26, 34, 36, 64, 66, 74, 76, 84, 86, 114, 116, 124, 126, 134, 136, 164, 166, 174, 176, 184, 186, 214, 216, 224, 226, 234, 236, 264, 266, 274, 276, 284, 286, 314, 316, 324, 326, 334, 336, 364, 366, 374, 376, 384, 386, 414, 416, 424, 426, 434
OFFSET
1,1
LINKS
FORMULA
a(n) = sqrt(A192689(n)).
EXAMPLE
34 is in the sequence because 34^2 = 1156 but neither 156, 56 nor 6 are perfect squares.
36 is in the sequence because 36^2 = 1296 but neither 296, 96 nor 6 are perfect squares.
44 is not in the sequence because 44^2 = 1936 and 36 = 6^2.
MATHEMATICA
nfgsQ[n_]:=Module[{s=n^2}, NoneTrue[FromDigits/@Rest[NestList[ Rest, IntegerDigits[ s], IntegerLength[ s]-1]], IntegerQ[Sqrt[#]]&]]; Select[ Range[ 4, 500], nfgsQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 18 2019 *)
CROSSREFS
Cf. A192689.
Sequence in context: A139061 A029645 A191208 * A050162 A345972 A224678
KEYWORD
nonn,base
AUTHOR
J. Lowell, May 03 2014
STATUS
approved