A225937 Number of conjugacy classes in adjoint Chevalley group E_7(q) as q runs through the prime powers.

531, 4569, 24553, 105644, 992834, 2447517, 5477205, 21674822, 68494004, 287617189, 437805224, 946620206, 3567305234, 6369359984, 10879403385, 17889596996, 28462405562, 35505127221, 97646355404, 199751157632, 278452165094, 517886829194, 692659723976

Offset

1,1

Links

Eric M. Schmidt, Table of n, a(n) for n = 1..1000

Frank Luebeck, Numbers of Conjugacy Classes in Finite Groups of Lie Type.

Formula

Let q be the n-th prime power. Then, a(n) is

q^7 + q^6 + 2q^5 + 4q^4 + 10q^3 + 15q^2 + 25q + 21 if q == 0 (mod 2);

q^7 + q^6 + 2q^5 + 5q^4 + 13q^3 + 24q^2 + 46q + 57 if q == 0 (mod 3);

q^7 + q^6 + 2q^5 + 5q^4 + 13q^3 + 24q^2 + 47q + 59 otherwise.

Prog

(Sage) def A225937(q) : return q^7 + q^6 + 2*q^5 + (4*q^4 + 10*q^3 + 15*q^2 + 25*q + 21 if q%2==0 else 5*q^4 + 13*q^3 + 24*q^2 + 46*q + 57 if q%3==0 else 5*q^4 + 13*q^3 + 24*q^2 + 47*q + 59)

Crossrefs

Cf. A188161, A224790, A225928 - A225938.

Sequence in context: A156772 A031701 A158367 * A225936 A098257 A174780

Adjacent sequences: A225934 A225935 A225936 * A225938 A225939 A225940

Keyword

nonn

Author

Eric M. Schmidt, May 21 2013

Status

approved