A328256 Amicable pairs of cyclops numbers.

1280565, 1340235, 71526069316, 75257076284, 1453520375775, 1561230417825, 1568650892445, 1995690781539, 2714480497936, 2854320218864, 5776910172896, 5864460215584, 5818350517628, 6516910297732, 6111770382135, 6139270339785, 9176850735616, 9194440569344, 114552504952875, 123277906567125

Offset

1,1

Comments

Amicable pairs (A259180) where both members are cyclops numbers (A134808).

Is this sequence finite? What is the largest known pair?

Up to 2^64 there are 439 pairs, the largest of them is {9591988390446931328, 9596251990981497472} (Eldar).

Links

Amiram Eldar, Table of n, a(n) for n = 1..878

OEIS Wiki, Cyclops Numbers

Example

{1280565, 1340235} is the first amicable pair where both members are cyclops numbers, so a(1) = 1280565 and a(2) = 1340235.

Crossrefs

Subsequence of A259180.

Cf. A002025, A002046, A134808, A262622, A262623.

Sequence in context: A147670 A204397 A058894 * A118419 A250619 A091291

Adjacent sequences: A328253 A328254 A328255 * A328257 A328258 A328259

Keyword

nonn,base

Author

Omar E. Pol, Oct 09 2019

Extensions

More terms from Amiram Eldar, Oct 09 2019

Status

approved