A225535 -id:A225535 - cp's OEIS frontend

A225534 Numbers whose sum of cubed digits is prime.

11, 101, 110, 111, 113, 115, 122, 124, 128, 131, 139, 142, 146, 148, 151, 155, 164, 166, 182, 184, 193, 199, 212, 214, 218, 221, 223, 227, 232, 236, 238, 241, 245, 254, 256, 263, 265, 269, 272, 278, 281, 283, 287, 289, 296, 298, 311, 319, 322, 326, 328, 335

Offset: 1

Kevin L. Schwartz and Christian N. K. Anderson, May 10 2013

Note that 11 is the only two-digit number in the sequence.

a(n) ~ n. For 414 < n < 10000, 6.38*n - 528 provides an estimate of a(n) to within 6%.

			139 is in the sequence because 1^3 + 3^3 + 9^3 = 757, which is prime.

Christian N. K. Anderson, Table of n, a(n) for n = 1..10000

Cf. A197039, A055012, A046459, A225535.
Cf. A165330, A046197.
Cf. A046704, A023194.

Select[Range[350],PrimeQ[Total[IntegerDigits[#]^3]]&] (* Harvey P. Dale, Mar 16 2016 *)

digcubesum<-function(x) sum(as.numeric(strsplit(as.character(x),split="")[[1]])^3); library(gmp);
which(sapply(1:1000,function(x) isprime(digcubesum(x))>0))

A254960 Zeroless numbers n with digits d_1, d_2, ... d_k such that d_1^3 + ... + d_k^3 is a cube.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 168, 186, 345, 354, 435, 453, 534, 543, 618, 681, 816, 861, 1156, 1165, 1516, 1561, 1615, 1651, 5116, 5161, 5611, 6115, 6151, 6511, 11233, 11323, 11332, 12133, 12313, 12331, 13123, 13132, 13213, 13231, 13312, 13321, 13369, 13396, 13458, 13485, 13548, 13584, 13639, 13693, 13845, 13854

Offset: 1

Derek Orr, Feb 11 2015

Any one of these terms can have an arbitrary number of 0's in between any two digits. Thus, the numbers with 0's have been omitted as trivial.

Jonathan Schwartz, Table of n, a(n) for n = 1..1000

Cf. A000578, A225535.

Select[Range[14000],DigitCount[#,10,0]==0&&IntegerQ[Surd[Total[ IntegerDigits[ #]^3],3]]&] (* Harvey P. Dale, Sep 23 2019 *)

for(n=1,10^3,d=digits(n);if(vecsort(d,,8)[1],s=0;for(i=1,#d,s+=d[i]^3);if(ispower(s,3),print1(n,", "))))

cp's OEIS Frontend

A225534 Numbers whose sum of cubed digits is prime.

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