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A211877
Number of involutions in GL(n,4).
1
1, 21, 673, 102273, 47663617, 110981851137, 815432848809985, 30052835284679819265, 3519512226295269640765441, 2069751512310185039905834926081, 3874510079394593253089862950754189313, 36431456010689490638771956423547489198538753
OFFSET
1,2
LINKS
MAPLE
A211877 := proc(n)
add( 4^(k*(n-k))*A022168(n, k), k=1..n) ;
end proc: # R. J. Mathar, Apr 26 2013
MATHEMATICA
Sum[q^(k (n - k)) QBinomial[n, k, q], {k, 1, n}]
CROSSREFS
Sequence in context: A020246 A239099 A006934 * A212734 A339119 A243746
KEYWORD
nonn
AUTHOR
Alexander Gruber, Feb 12 2013
STATUS
approved