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A363909
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Numbers whose square and cube taken together contain each decimal digit at least twice.
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1
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6534, 11027, 11994, 21906, 22178, 22195, 23317, 24567, 27019, 27963, 28354, 29099, 29309, 29339, 29375, 29558, 29621, 30184, 30552, 30584, 31578, 31727, 32447, 32633, 32793, 32912, 32923, 33087, 33257, 33527, 34284, 35717, 36943, 36958, 37697, 38463
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OFFSET
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1,1
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COMMENTS
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The first term, a(1) = 6534 is the only number of which the square and cube taken together contain each digit 0 to 9 exactly twice.
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LINKS
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EXAMPLE
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6534^2 = 42693156, 6534^3 = 278957081304, which together contain each digit 0-9 exactly twice.
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PROG
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(PARI) is(n)=#Set(n=concat(digits(n^2), digits(n^3)))>9&&(n=vecsort(n))[#n-1]==9&&!n[2]&&!for(i=3, #n-2, n[i]>n[i-1]&&n[i]<n[i+1]&&return)
select(is, [2111..39999])
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CROSSREFS
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Cf. A363905: square and cube together contain each digit at least once.
Cf. A119735: Numbers n such that every digit occurs at least once in n^3.
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KEYWORD
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nonn,base,less
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AUTHOR
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STATUS
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approved
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