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Search: id:A055012
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| A055012 |
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Sum of cubes of digits of n. |
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+0
12
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| 0, 1, 8, 27, 64, 125, 216, 343, 512, 729, 1, 2, 9, 28, 65, 126, 217, 344, 513, 730, 8, 9, 16, 35, 72, 133, 224, 351, 520, 737, 27, 28, 35, 54, 91, 152, 243, 370, 539, 756, 64, 65, 72, 91, 128, 189, 280, 407, 576, 793, 125, 126, 133, 152, 189, 250, 341, 468, 637, 854
(list; graph; listen)
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OFFSET
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0,3
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COMMENT
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For n > 1999, a(n) < n. The iteration of this map on n either stops at a fixed point (A046197) or has a period of length 2 or 3: {55,250,133}, {136,244}, {160,217,352}, or {919,1459}. - T. D. Noe, Jul 17 2007
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LINKS
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T. D. Noe, Table of n, a(n) for n=0..11000
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FORMULA
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A055012(n) = n iff n is in A046197 = {0, 1, 153, 370, 371, 407}. - Jonathan Vos Post (jvospost2(AT)yahoo.com), Mar 18 2006
a(n)=sum{k>0, (floor(n/10^k)-10*floor(n/10^(k+1)))^3}. - Hieronymus Fischer (Hieronymus.Fischer(AT)gmx.de), Jun 25 2007
a(10n+k)=a(n)+k^3, 0<=k<10. - Hieronymus Fischer (Hieronymus.Fischer(AT)gmx.de), Jun 25 2007
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MAPLE
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for n from 0 to 5 do seq(n^3+j^3, j=0..9 ); od; - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Nov 06 2006
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CROSSREFS
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Cf. A003132.
Cf. A046197 Fixed points for operation of repeatedly replacing a number by the sum of the cubes of its digits; A046459 The only integers equal to the sum of the digits of their cubes; A072884 3rd order digital invariants: the sum of the cubes of the digits of n equals some number k and the sum of the cubes of the digits of k equals n; A061212 cubes with the property that the sum of the cubes of the digits is also a cube.
Cf. A003132.
Cf. A007953, A055017, A076313, A076314.
Sequence in context: A017670 A126200 A076989 this_sequence A069939 A118880 A048390
Adjacent sequences: A055009 A055010 A055011 this_sequence A055013 A055014 A055015
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KEYWORD
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base,nonn
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AUTHOR
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Henry Bottomley (se16(AT)btinternet.com), May 31 2000
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