A375333 a(n) is the smallest number which can be represented as the sum of 6 distinct positive n-th powers in exactly 4 ways, or -1 if no such number exists.

-1, 187, 2492, 56290, 24993485, 2063792939

Offset: 1

Author

Ilya Gutkovskiy, Aug 12 2024

Keywords

• sign
• hard
• more

Examples

			a(6) = 2063792939 = 1^6 + 4^6 + 16^6 + 21^6 + 31^6 + 32^6
                  = 4^6 + 7^6 + 20^6 + 22^6 + 29^6 + 33^6
                  = 5^6 + 7^6 + 16^6 + 25^6 + 30^6 + 32^6
                  = 5^6 + 8^6 + 14^6 + 27^6 + 29^6 + 32^6.
		

Crossrefs

Cf. A046881, A342900, A374418, A374421, A374422, A374423, A374424, A374425, A375329, A375330, A375331, A375332, A375334.