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 A193759 #38 Mar 30 2012 18:40:59 %S A193759 0,0,1,0,1,1,0,1,1,2,0,1,1,2,1,0,1,1,3,1,2,0,1,2,2,1,2,1,0,1,2,2,2,3, %T A193759 1,3,0,1,2,2,2,3,2,2,2,0,1,2,6,2,4,3,3,2,2,0,1,3,5,2,4,3,3,3,3,1,3,0, %U A193759 1,4,7,3,4,3,4,3,2,2,2,1,0,1,5 %N A193759 Array, by antidiagonals, A(k,n) is the number of prime factors of n^(2^k) + 1, counted with multiplicity. %C A193759 The main diagonal A(n,n) = number of prime factors of n^(2^n) + 1, counted with multiplicity, begins 0, 1, 1, 3, 2, 4, 3, 6, 6. %e A193759 A(4,5) = 3 because 1+5^16 = 152587890626 = 2 * 2593 * 29423041, which has 3 prime factors. The array begins: %e A193759 ================================================================ %e A193759 ....|n=0|n=1|n=2|n=3|n=4|n=5|n=6|n=7|n=8|n=9|.10|.11|comment %e A193759 ====|===|===|===|===|===|===|===|===|===|===|===|===|=========== %e A193759 k=0.|.0.|.1.|.1.|.2.|.1.|.2.|.1.|.3.|.2.|.2.|.1.|.3.|A001222 %e A193759 k=1.|.0.|.1.|.1.|.2.|.1.|.2.|.1.|.3.|.2.|.2.|.1.|.2.|A193330 %e A193759 k=2.|.0.|.1.|.1.|.2.|.1.|.2.|.1.|.2.|.2.|.3.|.2.|.2.|A193929 %e A193759 k=3.|.0.|.1.|.1.|.3.|.1.|.3.|.2.|.3.|.3.|.2.|.2.|.3.|A194003 %e A193759 k=4.|.0.|.1.|.1.|.2.|.2.|.3.|.3.|.3.|.3.|.2.|.5.|.3.|not in OEIS %e A193759 k=5.|.0.|.1.|.2.|.2.|.2.|.4.|.3.|.4.|.3.|.2.|.4.|.4.|not in OEIS %e A193759 ================================================================ %Y A193759 Cf. A001222, A002523, A060890, A193330, A193929, A194003. %K A193759 nonn,hard,tabl %O A193759 0,10 %A A193759 _Jonathan Vos Post_, Aug 11 2011 %E A193759 Edited by _Alois P. Heinz_, Aug 11 2011 %E A193759 More terms from _Max Alekseyev_, Sep 09 2011