32,3
It is unknown whether a circular permutation of the numbers 1 to n exists such that the sum of any two consecutive numbers is a cube.
According to Rivera's Puzzle 311, the smallest n for which a cubic loop exists is 473. - T. D. Noe, Nov 26 2007
Table of n, a(n) for n=32..52.
Carlos Rivera, Puzzle 311: Sum to a cube
There is only one possible square loop of minimum length, which is: (32, 4, 21, 28, 8, 1, 15, 10, 26, 23, 2, 14, 22, 27, 9, 16, 20, 29, 7, 18, 31, 5, 11, 25, 24, 12, 13, 3, 6, 30, 19, 17) so a(32)=1.
Cf. A071983, A112663.
Sequence in context: A224405 A201150 A114030 * A211614 A101094 A187693
Adjacent sequences: A071981 A071982 A071983 * A071985 A071986 A071987
nice,nonn
William Rex Marshall, Jun 16 2002
a(48)-a(49) from Donovan Johnson, Sep 14 2010
a(50)-a(52) from Giovanni Resta, Nov 11 2012
approved
