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%I #6 Aug 08 2015 22:31:44
%S 1,2,63,14484,2422068105,30111613454906481726,
%T 4390292266180212777245130215697390895347,
%U 59487847503720962523422176966532983367477017476875634528888280148817939875308968
%N Beginning with 1, a(n) = n times the digits of concatenation of a(1),a(2), ...a(n-1) read backwards.
%C a(9) has 160 digits, a(10) has 320 digits. - _R. J. Mathar_, Feb 13 2008
%e a(2) = 2*1 = 2, a(3) = 3*21 = 63, a(4) = 4*3621 = 14484.
%p A109667 := proc(n) option remember ; if n = 1 then 1; else digs := [] ; for i from 1 to n-1 do digs := [op(digs),op(ListTools[Reverse](convert(A109667(i),base,10))) ] ; od: n*add(op(i,digs)*10^(i-1),i=1..nops(digs)) : fi ; end: seq(A109667(n),n=1..9) ; # _R. J. Mathar_, Feb 13 2008
%K base,easy,nonn
%O 1,2
%A _Amarnath Murthy_, Aug 03 2005
%E More terms from _R. J. Mathar_, Feb 13 2008