A047698 - OEIS

A047698

Numbers that are the sum of four positive seventh powers in two or more ways.

2056364173794800, 12191487610289536, 263214614245734400, 696885239160606459, 1560510414117060608, 4497268448089227600, 18896044524917750533, 25704745581139341318, 26662783403703215232, 33691470623454003200, 44053472466326057527, 100502405478837434259

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..12.

D. J. Bernstein, Enumerating solutions to p(a) + q(b) = r(c) + s(d)

R. L. Ekl, New Results in Equal Sums of Like Powers, Math. Comput. 67, 1309-1315, 1998.

EXAMPLE

4497268448089227600 = 30^7 + 42^7 + 369^7 + 447^7 = 45^7 + 270^7 + 387^7 + 438^7. - Sean A. Irvine, May 15 2021

CROSSREFS

Cf. A025367, A025406, A309763.

Sequence in context: A335044 A216910 A309111 * A246252 A058445 A290540