

A048926


Numbers that are the sum of 5 positive cubes in exactly 1 way.


8



5, 12, 19, 26, 31, 33, 38, 40, 45, 52, 57, 59, 64, 68, 71, 75, 78, 82, 83, 89, 90, 94, 96, 97, 101, 108, 109, 115, 116, 120, 127, 129, 131, 134, 135, 136, 138, 143, 145, 146, 150, 152, 153, 155, 162, 164, 169, 171, 172, 176, 181, 183, 188, 190, 192, 194, 195
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OFFSET

1,1


COMMENTS

It appears that this sequence has 11062 terms, the last of which is 1685758. This means that all numbers greater than 1685758 can be written as the sum of five positive cubes in at least two ways.  T. D. Noe, Dec 13 2006


LINKS



MATHEMATICA

Select[ Range[200], Count[ PowersRepresentations[#, 5, 3], r_ /; FreeQ[r, 0]] == 1 &] (* JeanFrançois Alcover, Oct 23 2012 *)


PROG

(Python)
from collections import Counter
from itertools import combinations_with_replacement as combs_with_rep
def aupto(lim):
s = filter(lambda x: x<=lim, (i**3 for i in range(1, int(lim**(1/3))+2)))
s2 = filter(lambda x: x<=lim, (sum(c) for c in combs_with_rep(s, 5)))
s2counts = Counter(s2)
return sorted(k for k in s2counts if s2counts[k] == 1)


CROSSREFS

Cf. A057906 (numbers not the sum of five positive cubes)


KEYWORD

nonn,fini


AUTHOR



STATUS

approved



