A096905 A card-arranging problem: values of n such that there exists a permutation p_1, ..., p_n of 1, ..., n such that i + p_i is a fourth power for every i.

15, 65, 80, 175, 190, 240, 255, 369, 384, 434, 449, 544, 559, 609, 624, 671, 686, 736, 751, 846, 861, 911, 926, 1040, 1055, 1105, 1120, 1215, 1230, 1235, 1250, 1260, 1270, 1275, 1280, 1285, 1290, 1295, 1300, 1305, 1315, 1345, 1360, 1474, 1489, 1519, 1529, 1534, 1539

Offset

1,1

Comments

1280 is the first n that has multiple solutions; it has 32. 1285 has 1024 solutions. 1290 has 248832 solutions. - David Wasserman, Dec 19 2007

Links

Table of n, a(n) for n=1..49.

Crossrefs

Cf. A006063, A096906.

Sequence in context: A118861 A118531 A144710 * A147857 A147858 A364401

Adjacent sequences: A096902 A096903 A096904 * A096906 A096907 A096908

Keyword

nonn

Author

Ray Chandler, Aug 02 2004

Extensions

More terms from David Wasserman, Nov 21 2007

Status

approved