This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A036261 #31 Sep 25 2023 19:19:14 %S A036261 1,1,2,1,0,2,1,2,2,4,1,2,0,2,2,1,2,0,0,2,4,1,2,0,0,0,2,2,1,2,0,0,0,0, %T A036261 2,4,1,2,0,0,0,0,0,2,6,1,0,2,2,2,2,2,2,4,2,1,0,0,2,0,2,0,2,0,4,6,1,0, %U A036261 0,0,2,2,0,0,2,2,2,4,1,0,0,0,0,2,0,0,0,2,0,2,2,1,0,0,0,0,0,2,2,2,2,0,0,2,4 %N A036261 Triangle of numbers arising from Gilbreath's conjecture: successive absolute differences of primes (read by antidiagonals upwards, omitting the initial row of primes). %C A036261 A variant of A036262, which is the main entry for this array. %D A036261 R. K. Guy, Unsolved Problems Number Theory, A10. %D A036261 C. A. Pickover, The Math Book, Sterling, NY, 2009; see p. 410. %H A036261 T. D. Noe, <a href="/A036261/b036261.txt">Rows n=1..100 of triangle, flattened</a> %H A036261 A. M. Odlyzko, <a href="http://dx.doi.org/10.1090/S0025-5718-1993-1182247-7">Iterated absolute values of differences of consecutive primes</a>, Math. Comp. 61 (1993), 373-380. %H A036261 Wikipedia, <a href="https://en.wikipedia.org/wiki/Gilbreath%27s_conjecture">Gilbreath's conjecture</a>. %H A036261 <a href="/index/Ge#Gilbreath">Index entries for sequences related to Gilbreath conjecture and transform</a> %e A036261 Table begins (conjecture is leading term is always 1): %e A036261 2 3 5 7 11 13 17 19 23 ... %e A036261 1 2 2 4 2 4 2 4 ... %e A036261 1 0 2 2 2 2 2 ... %e A036261 1 2 0 0 0, 0 ... %e A036261 1 2 0 0 0 ... %e A036261 1 2 0 0 ... %e A036261 ... %t A036261 max = 15; triangle = Rest[ NestList[ Abs[ Differences[#] ]& , Prime[ Range[max] ], max] ]; Flatten[ Table[ triangle[[n-k+1, k]], {n, 1, max-1}, {k, 1, n}]] (* _Jean-François Alcover_, Jan 23 2012 *) %Y A036261 Cf A036262. %K A036261 tabl,easy,nice,nonn %O A036261 1,3 %A A036261 _N. J. A. Sloane_ %E A036261 More terms from _Naohiro Nomoto_, May 22 2001