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A064399
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Numbers k whose sum of digits exceeds the sum of the digits of k^2.
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6
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39, 48, 49, 79, 149, 179, 249, 318, 348, 349, 389, 390, 399, 448, 449, 480, 489, 490, 498, 499, 548, 549, 579, 649, 679, 749, 789, 790, 795, 799, 849, 889, 895, 898, 899, 949, 1049, 1096, 1149, 1249, 1429, 1488, 1489, 1490, 1497, 1498, 1499, 1735, 1739
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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Select[ Range[ 2500 ], Apply[ Plus, IntegerDigits[ # ] ] > Apply[ Plus, IntegerDigits[ #^2 ] ] & ]
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PROG
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(PARI) SumD(x)= { local(s); s=0; while (x>9, s+=x-10*(x\10); x\=10); return(s + x) } { n=0; for (m=1, 10^9, if (SumD(m) > SumD(m^2), write("b064399.txt", n++, " ", m); if (n==1000, break)) ) } \\ Harry J. Smith, Sep 13 2009
(PARI) isok(n) = sumdigits(n) > sumdigits(n^2); \\ Michel Marcus, Jun 24 2018
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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STATUS
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approved
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