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 A271710 #22 Apr 15 2016 13:46:21 %S A271710 0,3,3,5,0,5,9,6,6,9,17,10,0,10,17,33,18,12,12,18,33,65,34,20,0,20,34, %T A271710 65,129,66,36,24,24,36,66,129,257,130,68,40,0,40,68,130,257,513,258, %U A271710 132,72,48,48,72,132,258,513,1025,514,260,136,80,0,80,136,260 %N A271710 Table T(n,k) = 2^n XOR 2^k read by antidiagonals, where XOR is the binary exclusive or operator. %C A271710 n > 1 is in this sequence if and only if it is in A018900. %H A271710 Peter Kagey, <a href="/A271710/b271710.txt">Table of n, a(n) for n = 0..10000</a> %F A271710 T(n, k) = 0 if n = k. %F A271710 T(n, k) = A271709(n, k) if n != k. %e A271710 a(0) = T(0, 0) = 2^0 XOR 2^0 = 0. %e A271710 a(1) = T(1, 0) = 2^1 XOR 2^0 = 3. %e A271710 0, 3, 5, 9, 17, 33, 65, 129, 257, 513,1025, %e A271710 3, 0, 6, 10, 18, 34, 66, 130, 258, 514,1026, %e A271710 5, 6, 0, 12, 20, 36, 68, 132, 260, 516,1028, %e A271710 9, 10, 12, 0, 24, 40, 72, 136, 264, 520,1032, %e A271710 17, 18, 20, 24, 0, 48, 80, 144, 272, 528,1040, %e A271710 33, 34, 36, 40, 48, 0, 96, 160, 288, 544,1056, %e A271710 65, 66, 68, 72, 80, 96, 0, 192, 320, 576,1088, %e A271710 129, 130, 132, 136, 144, 160, 192, 0, 384, 640,1152, %e A271710 257, 258, 260, 264, 272, 288, 320, 384, 0, 768,1280, %e A271710 513, 514, 516, 520, 528, 544, 576, 640, 768, 0,1536, %e A271710 1025,1026,1028,1032,1040,1056,1088,1152,1280,1536, 0, %p A271710 read("transforms") ; %p A271710 A271710 := proc(n,k) %p A271710 XORnos(2^n,2^k) ; %p A271710 end proc: # _R. J. Mathar_, Apr 15 2016 %t A271710 Table[BitXor[2^(n - k), 2^k], {n, 0, 10}, {k, 0, n}] // Flatten (* _Michael De Vlieger_, Apr 12 2016 *) %o A271710 (PARI) T(n, k) = bitxor(2^n, 2^k); %o A271710 matrix(10, 10, n, k, n--; k--; T(n,k)) \\ _Michel Marcus_, Apr 12 2016 %Y A271710 Cf. A271709. %K A271710 nonn,tabl,easy %O A271710 0,2 %A A271710 _Peter Kagey_, Apr 12 2016