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A393280
Minimum k such that k^6 can be expressed as the sum of n distinct positive 6th powers.
11
1141, 251, 123, 54, 53, 46, 43, 42, 35, 25, 32, 37, 41, 48, 49, 49, 49, 48, 45, 47, 48, 52, 55, 55, 53, 50, 55, 59, 57, 65, 67, 63, 66, 65, 68, 67, 71, 73, 77, 79, 79, 81, 81, 81, 83, 85, 89, 90, 90, 93, 94, 94, 96, 100, 104, 104, 104, 105, 103, 105, 108, 111
OFFSET
7,1
LINKS
Zhao Hui Du, Table of n, a(n) for n = 7..199 (terms 7..87 from Zhining Yang)
Eric Weisstein's World of Mathematics, Diophantine Equation--6th Powers.
EXAMPLE
a(7) = 1141 because 1141^6 = 1077^6 + 894^6 + 702^6 + 474^6 + 402^6 + 234^6 + 74^6 and no integer smaller than 1141 can be expressed as the sum of 7 distinct positive 6th powers.
a(9) = 123 because 123^6 = 112^6 + 106^6 + 62^6 + 46^6 + 40^6 + 22^6 + 8^6 + 5^6 + 4^6 and no integer smaller than 123 can be expressed as the sum of 9 distinct positive 6th powers.
MATHEMATICA
a[n_]:=FirstCase[Range[n+1, 60], k_/; Length[Select[IntegerPartitions[k^6, {n}, Range[k-1]^6], DuplicateFreeQ]]>0]; a[12]
KEYWORD
nonn
AUTHOR
Zhining Yang, Apr 08 2026
EXTENSIONS
a(49) and a(61) corrected by Zhao Hui Du, Apr 16 2026
STATUS
approved