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A353291
Integers whose cube is the sum of the cubes of four primes, not necessarily distinct.
1
12, 66, 336, 504, 588, 602, 756, 1092, 1248, 1470, 1638, 1848, 2142, 2184, 2289, 2394, 2772, 3094, 3192, 3276, 3885, 3948, 4242, 4284, 4368, 4410, 4578, 4620, 4788, 4830, 4998, 5166, 5460, 5544, 5586, 5670, 5754, 6006, 6216, 6552, 6636, 6708, 6804, 6930, 7014
OFFSET
1,1
LINKS
Michael S. Branicky, Table of n, a(n) for n = 1..53
Zhichun Zhai, Problems related to Waring-Goldbach problem involving cubes of primes, arXiv:2201.07346 [math.GM], 2022. See Table 3 p. 4.
EXAMPLE
12 is a term because 3^3 + 3^3 + 7^3 + 11^3 = 1728 = 12^3.
PROG
(PARI) list(lim)=my(v=List(), P=apply(p->p^3, primes(sqrtnint(lim\=1, 3)))); foreach(P, p, foreach(P, q, foreach(P, r, my(s=p+q+r, t); for(i=1, #P, t=s+P[i]; if(t>lim, break); if (ispower(t, 3, &rr), listput(v, rr)))))); v = Set(v);
CROSSREFS
Cube roots of the intersection of A346917 and A000578.
Sequence in context: A161805 A036399 A003200 * A200190 A270251 A165107
KEYWORD
nonn
AUTHOR
Michel Marcus, Apr 09 2022
EXTENSIONS
a(8) and beyond from Michael S. Branicky, Apr 09 2022
STATUS
approved