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%I #7 Nov 01 2019 16:42:03
%S 2,9,12,36,48,64,128,256,512,1024,2048,4096,8192,16384,32768,65536,
%T 131072,262144,524288,1048576,2097152,4194304,8388608,16777216,
%U 33554432,67108864,134217728,268435456,536870912,1073741824,2147483648
%N Smallest number equal to the product of n primes which is also equal to the sum of n distinct primes.
%C Conjecture: a(n) = 2^n for n>5. - _Ray Chandler_ Feb 25 2005
%e a(1) = 2;
%e a(2) = 9 = 3*3 = 2+7;
%e a(3) = 12 = 2*2*3 = 2+3+7;
%e a(4) = 36 = 2*2*3*3 = 3+5+11+17;
%e a(5) = 48 = 2*2*2*2*3 = 2+3+5+7+31.
%K nonn
%O 1,1
%A _Giovanni Teofilatto_, Feb 18 2005
%E Corrected and extended by _Ray Chandler_ Feb 25 2005