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A133785
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Numbers n such that integer part of the square root of n appears as a substring in n.
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2
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1, 13, 24, 25, 35, 36, 46, 57, 68, 78, 80, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 214, 317, 420, 522, 624, 625, 726, 828, 930, 1032, 1133, 1235, 1336, 1360, 1361, 1362, 1363, 1364, 1365, 1366, 1367
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OFFSET
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1,2
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COMMENTS
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Includes all numbers from 10^(2*k)-10^k to 10^(2*k)+10^k. - Robert Israel, Nov 11 2018
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LINKS
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EXAMPLE
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a(2)=13 because int(sqrt(13))=3 and "3" occurs in "13".
a(7)=46 because int(sqrt(46))=6 and "6" occurs in "46".
a(38)=624 because int(sqrt(624))=24 and "24" occurs in "624".
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MAPLE
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filter:= proc(n) local S, T;
S:= sprintf("%d", n);
T:= sprintf("%d", floor(sqrt(n)));
StringTools[Search](T, S) <> 0
end proc:
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PROG
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FOR i& = 1 TO 1000000 s$ = MID$(STR$(INT(SQR(i&))), 2) IF INSTR(STR$(i&), s$) > 0 THEN PRINT i& END IF NEXT i&
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CROSSREFS
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KEYWORD
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easy,nonn,base
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AUTHOR
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STATUS
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approved
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