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%I #14 Feb 03 2019 17:02:51
%S 0,0,0,0,0,0,0,0,0,0,0,3,0,5,0,0,0,0,3,0,0,0,7,0,0,0,0,0,0,5,0,7,0,0,
%T 0,0,0,0,3,0,0,0,0,0,0,0,11,0,0,0,0,3,0,5,0,0,0,0,0,11,0,13,0,0,0,0,0,
%U 0,5,0,7,0,0,0,11,0,13,0,0,0,0
%N Triangle read by rows in which row n lists 2n-1 terms: The pairs of prime numbers that are equidistant to n, with 0's inserted, as shown below in the example.
%C Each entry of the n-th row is either 0 or a prime p from the 2n-th row of A002260 such that 2n-p is also prime. - _Jason Kimberley_, Jul 08 2012
%H Nathaniel Johnston, <a href="/A154725/b154725.txt">Table of n, a(n) for n = 1..10000</a>
%e Triangle begins:
%e 0
%e 0, 0, 0
%e 0, 0, 0, 0, 0
%e 0, 0, 3, 0, 5, 0, 0
%e 0, 0, 3, 0, 0, 0, 7, 0, 0
%e 0, 0, 0, 0, 5, 0, 7, 0, 0, 0, 0
%e 0, 0, 3, 0, 0, 0, 0, 0, 0, 0,11, 0, 0
%e 0, 0, 3, 0, 5, 0, 0, 0, 0, 0,11, 0,13, 0, 0
%e 0, 0, 0, 0, 5, 0, 7, 0, 0, 0,11, 0,13, 0, 0, 0, 0
%e 0, 0, 3, 0, 0, 0, 7, 0, 0, 0, 0, 0,13, 0, 0, 0,17, 0, 0
%e From _Jason Kimberley_, Jul 08 2012: (Start)
%e Square array begins:
%e 3, 3, 3, 0, 3, 3, 0, 3, 3, ...
%e 0, 0, 0, 0, 0, 0, 0, 0, ...
%e 5, 5, 5, 0, 5, 5, 0, 5, ...
%e 0, 0, 0, 0, 0, 0, 0, ...
%e 7, 7, 7, 0, 7, 7, 0, ...
%e 0, 0, 0, 0, 0, 0, ...
%e 0, 0, 0, 0, 0, 0, ...
%e 0, 0, 0, 0, 0, ...
%e 11, 11, 11, 0, 11, ...
%e 0, 0, 0, 0, ...
%e 13, 13, 13, 0, ...
%e 0, 0, 0, ...
%e 0, 0, 0, ...
%e 0, 0, ...
%e 17, 17, ...
%e 0, ...
%e 19, ...
%p for n from 1 to 10 do for k from 1 to 2*n-1 do if(not k=n and (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, A154721, A154722, A154723, A154724, A154726, A154727.
%K easy,nonn,tabf
%O 1,12
%A _Omar E. Pol_, Jan 14 2009
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