A178400 - OEIS

%I #13 Mar 30 2012 18:57:11

%S 4,5,5,6,7,7,8,8,9,9,10,10,10,12,12,13,13,14,14,14,15,15,16,16,16,16,

%T 18,18,18,18,19,19,20,20,20,20,21,21,22,22,22,22,22,24,24,24,24,24,24,

%U 25,25,26,26,26,26,26,28,28,28,28,30,30,30,30,30,30,31

%N Sums of two primes, an array by antidiagonals.

%C The joint-rank array of this array is A178431.

%F T(i,j)=p(i)+p(j), where p=(2,3,5,7,...)=A000040.

%e Northwest corner:

%e 4....5....7....9...13...

%e 5....6....8...10...12...

%e 7....8...10...12...16...

%e 9...10...12...14...14...

%e T(1,1)=2+2=4.

%Y Cf. A000040, A014092.

%K nonn,tabl

%O 1,1

%A _Clark Kimberling_, Dec 21 2010