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%I #22 Sep 10 2021 06:08:00
%S 4,5,6,7,8,10,9,10,12,14,13,14,16,18,22,15,16,18,20,24,26,19,20,22,24,
%T 28,30,34,21,22,24,26,30,32,36,38,25,26,28,30,34,36,40,42,46,31,32,34,
%U 36,40,42,46,48,52,58,33,34,36,38,42,44,48,50,54,60,62,39,40,42,44,48
%N Triangle of sum of two primes: prime(n)+prime(k) with n >= k >= 1.
%H Reinhard Zumkeller, <a href="/A065342/b065342.txt">First 125 rows of triangle, flattened</a>
%H <a href="/index/Go#Goldbach">Index entries for sequences related to Goldbach conjecture</a>
%F T(n, k) = 2*A065305(n, k) [but note different offset].
%e Sequence starts 2+2; 3+2, 3+3; 5+2, 5+3, 5+5; etc. i.e. 4; 5,6; 7,8,10; ...
%e Triangle begins:
%e 4;
%e 5, 6;
%e 7, 8, 10;
%e 9, 10, 12, 14;
%e 13, 14, 16, 18, 22;
%e ...
%o (Haskell)
%o import Data.List (inits)
%o a065342 n k = a065342_tabl !! (n-1) !! (k-1)
%o a065342_row n = a065342_tabl !! (n-1)
%o a065342_tabl = zipWith (map . (+)) a000040_list $ tail $ inits a000040_list
%o -- _Reinhard Zumkeller_, Aug 02 2015, Jan 30 2012
%o (PARI) row(n) = vector(n, k, prime(n)+prime(k)); \\ _Michel Marcus_, Sep 10 2021
%Y Cf. A052147 (left edge), A100484 (right edge), A000040.
%Y Cf. A087112.
%Y Cf. A065305.
%K nonn,tabl
%O 1,1
%A _Henry Bottomley_, Oct 30 2001
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