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for (U sub n) Un=3n-1, list U1+U2+U3+....+U20 and find its sum

 Sep 22, 2014

Best Answer 

 #1
avatar+26398 
+5

for (U sub n) Un=3n-1, list U1+U2+U3+....+U20 and find its sum

Un=3n1nUn12253841151461772082392610291132123513381441154416471750185319562059

sum:

2+5+8+11+14...47+50+53+56+5959+56+53+50+47...14+11+8+5+2sum61+61+61+61+61...61+61+61+61+61sum=122061=610

 Sep 22, 2014
 #1
avatar+26398 
+5
Best Answer

for (U sub n) Un=3n-1, list U1+U2+U3+....+U20 and find its sum

Un=3n1nUn12253841151461772082392610291132123513381441154416471750185319562059

sum:

2+5+8+11+14...47+50+53+56+5959+56+53+50+47...14+11+8+5+2sum61+61+61+61+61...61+61+61+61+61sum=122061=610

heureka Sep 22, 2014

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