A373514 Number of simple difference sets of the Singer type (m^2 + m + 1, m + 1, 1) that are a superset of {0, 1, 3} with m = m(n) = A000961(n), for n >= 1.

0, 1, 1, 0, 2, 1, 1, 1, 4, 3, 1, 6, 3, 8, 2, 3, 9, 6, 2, 8, 14, 10, 14, 4, 14, 20, 10, 2, 14, 24, 15, 18, 6, 27, 30, 19, 34, 21, 26, 22, 33, 10, 13, 30, 5, 44, 38, 30, 41, 26, 36, 25, 56, 17, 58, 52, 38, 51, 40, 63, 45, 41, 46, 76, 47, 70, 72, 55, 15, 80, 6

Offset

1,5

Links

Martin Becker, Table of n, a(n) for n = 1..400

Example

For n=5, m=5, there are 2 Singer type planar difference sets of order 5 containing 0, 1, and 3: {0,1,3,8,12,18} and {0,1,3,10,14,26}. Thus a(5) = 2.
For n=11, m=16, there is only 1 such set: {0,1,3,7,15,31,63,90,116,127,136,181,194,204,233,238,255}. Thus a(11) = 1.

Crossrefs

Cf. A335866, A000961, A373946. Counts sets in A333852 with the property that 3 is also in the set.

Sequence in context: A294895 A285328 A321030 * A290529 A266349 A219094

Adjacent sequences: A373511 A373512 A373513 * A373515 A373516 A373517

Keyword

nonn

Author

Martin Becker, Jun 07 2024

Status

approved