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A360306
a(n) is the smallest positive integer which can be represented as the sum of n distinct nonzero fourth powers in exactly n ways, or -1 if no such integer exists.
2
1, 635318657, 811538, 300834, 185299, 138595, 143651, 154292, 197748, 225733, 291269, 374790, 474071, 586056, 715192, 857513, 1057689, 1330554, 1602250, 1919146, 2329547, 2786843, 3246204, 3899260, 4642700, 5378141, 6377822, 7342638, 8527103, 9787839, 11241455, 12978656
OFFSET
1,2
LINKS
Bert Dobbelaere, C++ program
Eric Weisstein's World of Mathematics, Biquadratic Number
EXAMPLE
For n = 2: 635318657 = 59^4 + 158^4 = 133^4 + 134^4.
For n = 3: 811538 = 4^4 + 23^4 + 27^4 = 7^4 + 21^4 + 28^4 = 12^4 + 17^4 + 29^4.
For n = 4: 300834 = 1^4 + 4^4 + 12^4 + 23^4 = 1^4 + 16^4 + 18^4 + 19^4 = 3^4 + 6^4 + 18^4 + 21^4 = 7^4 + 14^4 + 16^4 + 21^4.
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Feb 02 2023
EXTENSIONS
a(18)-a(19) from Michael S. Branicky, Feb 04 2023
More terms from Bert Dobbelaere, Feb 11 2023
STATUS
approved