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%I #20 Mar 16 2016 16:15:44
%S 11,101,110,111,113,115,122,124,128,131,139,142,146,148,151,155,164,
%T 166,182,184,193,199,212,214,218,221,223,227,232,236,238,241,245,254,
%U 256,263,265,269,272,278,281,283,287,289,296,298,311,319,322,326,328,335
%N Numbers whose sum of cubed digits is prime.
%C Note that 11 is the only two-digit number in the sequence.
%C a(n) ~ n. For 414 < n < 10000, 6.38*n - 528 provides an estimate of a(n) to within 6%.
%H Christian N. K. Anderson, <a href="/A225534/b225534.txt">Table of n, a(n) for n = 1..10000</a>
%e 139 is in the sequence because 1^3 + 3^3 + 9^3 = 757, which is prime.
%t Select[Range[350],PrimeQ[Total[IntegerDigits[#]^3]]&] (* _Harvey P. Dale_, Mar 16 2016 *)
%o (R)
%o digcubesum<-function(x) sum(as.numeric(strsplit(as.character(x),split="")[[1]])^3); library(gmp);
%o which(sapply(1:1000,function(x) isprime(digcubesum(x))>0))
%Y Cf. A197039, A055012, A046459, A225535.
%Y Cf. A165330, A046197.
%Y Cf. A046704, A023194.
%K nonn,base
%O 1,1
%A _Kevin L. Schwartz_ and _Christian N. K. Anderson_, May 10 2013
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