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Triangle read by rows. Row 0 = {2}; left half of row n+1 = row n, right half = row n reversed with each term replaced by the next prime.
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%I #21 Oct 31 2023 15:42:02

%S 2,2,3,2,3,5,3,2,3,5,3,5,7,5,3,2,3,5,3,5,7,5,3,5,7,11,7,5,7,5,3,2,3,5,

%T 3,5,7,5,3,5,7,11,7,5,7,5,3,5,7,11,7,11,13,11,7,5,7,11,7,5,7,5,3,2,3,

%U 5,3,5,7,5,3,5,7,11,7,5,7,5,3,5,7,11,7,11,13,11,7,5,7,11,7,5,7,5,3,5,7,11,7

%N Triangle read by rows. Row 0 = {2}; left half of row n+1 = row n, right half = row n reversed with each term replaced by the next prime.

%C Row n has 2^n terms.

%C Row sums = (2, 5, 13, 33, 83, 205, 495,...) = A007443, the binomial transform of the primes.

%H Alois P. Heinz, <a href="/A164738/b164738.txt">Rows n = 0..13, flattened</a>

%e The triangle begins:

%e 2;

%e 2, 3;

%e 2, 3, 5, 3;

%e 2, 3, 5, 3, 5, 7, 5, 3;

%e 2, 3, 5, 3, 5, 7, 5, 3, 5, 7, 11, 7, 5, 7, 5, 3;

%e ...

%t Flatten[NestList[Join[ #, NextPrime[Reverse[ # ]]] &, {2}, 7]] (* _Zak Seidov_, Aug 24 2009 *)

%Y Cf. A000040, A007443, A088696.

%K nonn,tabf

%O 0,1

%A _Gary W. Adamson_, Aug 23 2009

%E More terms from _Zak Seidov_, Aug 24 2009

%E Edited by _Zak Seidov_ and _N. J. A. Sloane_, Aug 25 2009

%E Offset 0 from _Alois P. Heinz_, Oct 31 2023