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A109664
a(1) = 1; for n>1, a(n) = Sum_{i=1..n-1} a(i)*prime(i).
0
1, 2, 8, 48, 384, 4608, 64512, 1161216, 23224320, 557383680, 16721510400, 535088332800, 20333356646400, 854000979148800, 37576043082547200, 1803650067962265600, 97397103669962342400, 5843826220197740544000
OFFSET
1,2
MATHEMATICA
a[n_] := 1 /; n == 1 a[n_] := Sum[a[i]*Prime[i], {i, 1, n-1}] Table[a[i], {i, 1, 12}]
CROSSREFS
Sequence in context: A241122 A370677 A370936 * A009812 A232005 A351422
KEYWORD
easy,nonn
AUTHOR
Joseph L. Pe, Aug 06 2005
EXTENSIONS
More terms from Robert G. Wilson v, Aug 09 2005
STATUS
approved