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A062098
a(n) = 7 * n!.
3
7, 14, 42, 168, 840, 5040, 35280, 282240, 2540160, 25401600, 279417600, 3353011200, 43589145600, 610248038400, 9153720576000, 146459529216000, 2489811996672000, 44816615940096000, 851515702861824000
OFFSET
1,1
LINKS
Luis Manuel Rivera, Integer sequences and k-commuting permutations, arXiv preprint arXiv:1406.3081 [math.CO], 2014-2015.
FORMULA
a(n) = n*a(n-1), a(1) = 7.
a(n) = 7 * A000142(n) for n>0. - Michel Marcus, Aug 31 2013
MAPLE
G(x):=(x-8)/(1-x): f[0]:=G(x): for n from 1 to 19 do f[n]:=diff(f[n-1], x) od: x:=0: seq(-f[n], n=1..19); # Zerinvary Lajos, Apr 03 2009
MATHEMATICA
Array[7 #! &, 19] (* Michael De Vlieger, Jul 01 2018 *)
PROG
(PARI) { a=7; for (n=1, 100, write("b062098.txt", n, " ", a*=n) ) } \\ Harry J. Smith, Aug 01 2009
(GAP) List([1..20], n->7*Factorial(n)); # Muniru A Asiru, Jul 01 2018
CROSSREFS
Sequence in context: A067048 A189046 A098328 * A374509 A045759 A166637
KEYWORD
nonn,easy
AUTHOR
Dan Henry (daniel.henry(AT)umit.maine.com), Jun 28 2001
EXTENSIONS
More terms from Larry Reeves (larryr(AT)acm.org), Jul 05 2001
Offset changed from 7 to 1 by Harry J. Smith, Aug 01 2009
STATUS
approved