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Search: id:A061862
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| A061862 |
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Powerful numbers (2a): a sum of nonnegative powers of its digits. |
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+0
2
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| 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 24, 43, 63, 89, 132, 135, 153, 175, 209, 224, 226, 254, 258, 262, 263, 264, 267, 283, 332, 333, 334, 347, 357, 370, 371, 372, 373, 374, 375, 376, 377, 378, 379, 407, 445, 463, 472, 518, 538, 598, 629, 635, 653, 675, 730, 731, 732
(list; graph; listen)
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OFFSET
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1,3
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FORMULA
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If n = d_1 d_2 ... d_k in decimal then there are integers m_1 m_2 ... m_k >= 0 such that n = d_1^m_1 + ... + d_k^m_k.
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EXAMPLE
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43 = 4^2 + 3^3; 254 = 2^7 + 5^3 + 4^0 = 128 + 125 + 1.
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MATHEMATICA
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f[ n_ ] := Module[ {}, a=IntegerDigits[ n ]; e=g[ Length[ a ] ]; MemberQ[ Map[ Apply[ Plus, a^# ] &, e ], n ] ] g[ n_ ] := Map[ Take[ Table[ 0, {n} ]~Join~#, -n ] &, IntegerDigits[ Range[ 10^n ], 10 ] ] For[ n=0, n >= 0, n++, If[ f[ n ], Print[ n ] ] ]
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CROSSREFS
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Cf. A001694, A005934, A005188, A003321, A014576, A023052, A046074.
Different from A007532.
Sequence in context: A117732 A116960 A126957 this_sequence A007532 A068189 A069716
Adjacent sequences: A061859 A061860 A061861 this_sequence A061863 A061864 A061865
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KEYWORD
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base,nonn
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AUTHOR
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Erich Friedman (efriedma(AT)stetson.edu), Jun 23 2001
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