A225535 Numbers whose cubed digits sum to a cube, and have more than one nonzero digit.
168, 186, 345, 354, 435, 453, 534, 543, 618, 681, 816, 861, 1068, 1086, 1156, 1165, 1516, 1561, 1608, 1615, 1651, 1680, 1806, 1860, 3045, 3054, 3405, 3450, 3504, 3540, 4035, 4053, 4305, 4350, 4503, 4530, 5034, 5043, 5116, 5161, 5304, 5340, 5403, 5430, 5611
Offset: 1
Examples
5^3 + 6^3 + 1^3 + 1^3 = 343, which is 7^3.
Links
- Christian N. K. Anderson, Table of n, a(n) for n = 1..10000
Crossrefs
Cf. A164882 (n such that sum of the cubes of the digits of n^3 is perfect cube). - Zak Seidov, May 21 2013
Programs
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Mathematica
fQ[n_] := Module[{d = IntegerDigits[n]}, Count[d, 0] + 1 < Length[d] && IntegerQ[Total[d^3]^(1/3)]]; Select[Range[5611], fQ] (* T. D. Noe, May 19 2013 *) -
R
y=rep(0,10000); len=0; x=0; library(gmp); digcubesum<-function(x) sum(as.numeric(unlist(strsplit(as.character(as.bigz(x)),split="")))^3); iscube<-function(x) ifelse(as.bigz(x)<2,T,all(table(as.numeric(factorize(x)))%%3==0)); nonzerodig<-function(x) sum(strsplit(as.character(x),split="")[[1]]!="0"); which(sapply(1:6000,function(x) nonzerodig(x)>1 & iscube(digcubesum(x))))