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%I #11 Aug 17 2012 22:14:05
%S 2,3,4,5,7,9,10,13,17,19,25,28,33,37,49,55,65,73,82,97,109,129,145,
%T 163,193,217,244,257,289,325,385,433,487,513,577,649,730,769,865,973,
%U 1025,1153,1297,1459,1537,1729,1945,2049,2188,2305,2593,2917,3073,3457,3889
%N Numbers of form 2^i*3^j+1 with i, j >= 0.
%C If X is an n-set and Y a fixed (n-5)-subset of X then a(n-5) is equal to the number of 2-subsets of X intersecting Y. - _Milan Janjic_, Aug 15 2007
%D G. Everest, P. Rogers and T. Ward, A higher-rank Mersenne problem, pp. 95-107 of ANTS 2002, Lect. Notes Computer Sci. 2369 (2002).
%H Milan Janjic, <a href="http://www.pmfbl.org/janjic/">Two Enumerative Functions</a>
%F a(n)=A003586(n)+1
%e a(7)=13 since 13=2^2*3^1+1
%t mx = 4000; Sort@ Flatten@ Table[ 2^i*3^j + 1, {i, 0, Log[2, mx]}, {j, 0, Log[3, mx/2^i]}] (* _Robert G. Wilson v_, Aug 17 2012 *)
%Y Primes in this sequence give A005109 (Class 1- or Pierpoint primes).
%K easy,nonn
%O 0,1
%A _Henry Bottomley_, Jun 01 2000
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