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A225932
Number of conjugacy classes in simply connected Chevalley group E_6(q) as q runs through the prime powers.
1
180, 1269, 6116, 20454, 140886, 304548, 605685, 1965462, 5262486, 17969012, 25736406, 49802214, 155060070, 254728710, 402876885, 616803846, 918054582, 1109465220, 2638941366, 4871761782, 6475396806, 11018543046, 14135564454, 22598655270, 42920128086
OFFSET
1,1
FORMULA
Let q be the n-th prime power.
a(n) = q^6 + q^5 + 2q^4 + 2q^3 + 15q^2 + 21q + 60 if q == 1 (mod 6).
a(n) = q^6 + q^5 + 2q^4 + 2q^3 + 6q^2 + 4q + 4 if q == 2 (mod 6).
a(n) = q^6 + q^5 + 2q^4 + 2q^3 + 7q^2 + 5q + 3 if q == 3 (mod 6).
a(n) = q^6 + q^5 + 2q^4 + 2q^3 + 14q^2 + 20q + 52 if q == 4 (mod 6).
a(n) = q^6 + q^5 + 2q^4 + 2q^3 + 7q^2 + 5q + 4 if q == 5 (mod 6).
PROG
(Sage) def A225932(q) : return q^6 + q^5 + 2*q^4 + 2*q^3 + [15*q^2 + 21*q + 60, 6*q^2 + 4*q + 4, 7*q^2 + 5*q + 3, 14*q^2 + 20*q + 52, 7*q^2 + 5*q + 4][q%6-1]
CROSSREFS
KEYWORD
nonn
AUTHOR
Eric M. Schmidt, May 21 2013
STATUS
approved