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%I #9 Feb 03 2019 16:52:35
%S 1,0,2,0,0,0,3,0,0,0,0,3,4,5,0,0,0,0,3,0,5,0,7,0,0,0,0,0,0,5,6,7,0,0,
%T 0,0,0,0,3,0,0,0,7,0,0,0,11,0,0,0,0,3,0,5,0,0,8,0,0,11,0,13,0,0,0,0,0,
%U 0,5,0,7,0,9,0,11,0,13,0,0,0,0
%N Triangle read by rows in which row n lists 2n-1 terms: n, in the center of the row and the pairs of prime numbers that are equidistant to n, with 0's inserted, as shown below in the example.
%H Nathaniel Johnston, <a href="/A154724/b154724.txt">Table of n, a(n) for n = 1..10000</a>
%e Triangle begins:
%e 1
%e 0, 2, 0
%e 0, 0, 3, 0, 0
%e 0, 0, 3, 4, 5, 0, 0
%e 0, 0, 3, 0, 5, 0, 7, 0, 0
%e 0, 0, 0, 0, 5, 6, 7, 0, 0, 0, 0
%e 0, 0, 3, 0, 0, 0, 7, 0, 0, 0,11, 0, 0
%e 0, 0, 3, 0, 5, 0, 0, 8, 0, 0,11, 0,13, 0, 0
%e 0, 0, 0, 0, 5, 0, 7, 0, 9, 0,11, 0,13, 0, 0, 0, 0
%e 0, 0, 3, 0, 0, 0, 7, 0, 0,10, 0, 0,13, 0, 0, 0,17, 0, 0
%p for n from 1 to 10 do for k from 1 to 2*n-1 do if(k=n or (isprime(k) and isprime(2*n-k)))then print(k):else print(0):fi:od:od: # _Nathaniel Johnston_, Apr 18 2011
%Y Cf. A000040, A154720-A154727.
%K easy,nonn,tabf
%O 1,3
%A _Omar E. Pol_, Jan 14 2009
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