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A025412
Numbers that are the sum of 4 distinct positive cubes in 2 or more ways.
2
1036, 1134, 1352, 1367, 1430, 1465, 1484, 1521, 1547, 1582, 1638, 1709, 1736, 1764, 1800, 1801, 1820, 1862, 1863, 1881, 1918, 1953, 1972, 2009, 2070, 2080, 2099, 2136, 2197, 2249, 2268, 2288, 2305, 2331, 2340, 2366, 2422, 2457, 2464, 2483, 2485, 2520
OFFSET
1,1
LINKS
MAPLE
M:= 4000: # for terms <= M
V:= Vector(M):
for a from 1 while 4*a^3 < M do
for b from a+1 while a^3 + 3*b^3 < M do
for c from b+1 while a^3 + b^3 + 2*c^3 < M do
for d from c+1 do
v:= a^3 + b^3 + c^3 + d^3;
if v > M then break fi;
V[v]:= V[v]+1
od od od od:
select(t -> V[t] > 1, [$1..M]); # Robert Israel, Oct 23 2023
CROSSREFS
Sequence in context: A219445 A373407 A163558 * A025409 A043388 A184210
KEYWORD
nonn
STATUS
approved