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A076164
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Numbers n such that sum of squares of even digits of n equals sum of squares of odd digits of n.
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1
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0, 11112, 11121, 11211, 11356, 11365, 11536, 11563, 11635, 11653, 12111, 13156, 13165, 13516, 13561, 13615, 13651, 15136, 15163, 15316, 15361, 15613, 15631, 16135, 16153, 16315, 16351, 16513, 16531, 21111, 31156, 31165, 31516, 31561
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OFFSET
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1,2
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COMMENTS
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The minimal number of digits in any nonzero term is 5.
Numbers such that the sum of even digits equals the sum of odd digits are listed in A036301.
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LINKS
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EXAMPLE
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11356 is in the sequence because 1^2 + 1^2 + 3^2 + 5^2 = 6^2.
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MATHEMATICA
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oeQ[n_]:=Module[{idn=IntegerDigits[n]}, Total[Select[idn, OddQ]^2]== Total[ Select[ idn, EvenQ]^2]]; Select[Range[0, 99999], oeQ] (* Harvey P. Dale, Sep 23 2011 *)
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PROG
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(PARI) is(n)=!vecsum(apply(d->d^2*(-1)^d, digits(n))) \\ M. F. Hasler, May 18 2018
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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