document.write( "Question 361815: Find the sum of the rest 20 terms of the following series: 4 + 12 + 36 + 108... \n" ); document.write( "
Algebra.Com's Answer #257900 by robertb(5830)\"\" \"About 
You can put this solution on YOUR website!
4+12+36+108+... = 4(1+3+9+27 +...)
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\n" ); document.write( "= \"2%2A%283%5E21+-1%29\".
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