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 A372359 #7 May 01 2024 08:58:16 %S A372359 0,0,0,0,0,0,0,0,0,2,0,0,0,24,4,0,0,0,256,32,6,0,0,0,0,6144,16,0,0,0, %T A372359 0,0,16777216,0,0,2,0,0,0,0,0,0,0,8,4,0,0,0,0,0,0,0,1408,0,6,0,0,0,0, %U A372359 0,0,0,0,0,32,0,0,0,0,0,0,0,0,0,0,6144,0,2,0,0,0,0,0,0,0,0,0,16777216,0,88,12 %N A372359 Array read by upward antidiagonals: A(n, k) = A372358(A372282(n, k)), n,k >= 1. %C A372359 Zeros occur in the same locations as where they occur in A372353 and where 1's occur in array A372287. %F A372359 A(n, k) = A372282(n,k) XOR A086893(1+A372354(n, k)), where XOR is bitwise-xor, A003987. %e A372359 Array begins: %e A372359 n\k| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 %e A372359 ---+---------------------------------------------------------------------------- %e A372359 1 | 0, 0, 0, 2, 4, 6, 0, 2, 4, 6, 0, 2, 12, 14, %e A372359 2 | 0, 0, 0, 24, 32, 16, 0, 8, 0, 32, 0, 88, 96, 112, %e A372359 3 | 0, 0, 0, 256, 6144, 0, 0, 1408, 0, 6144, 0, 0, 8192, 2560, %e A372359 4 | 0, 0, 0, 0, 2^24, 0, 0, 0, 0, 2^24, 0, 0, 402653184, 6815744, %e A372359 5 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2^56, 4947802324992, %e A372359 6 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 31 * 2^79, %e A372359 where 2^56 = 72057594037927936 and 31 * 2^79 = 18738350204026752207945728. %o A372359 (PARI) %o A372359 up_to = 91; %o A372359 A000523(n) = logint(n,2); %o A372359 A086893(n) = (if(n%2, 2^(n+1), 2^(n+1)+2^(n-1))\3); \\ From A086893 %o A372359 A372358(n) = bitxor(A086893(1+A000523(n)),n); %o A372359 A371094(n) = { my(m=1+3*n, e=valuation(m,2)); ((m*(2^e)) + (((4^e)-1)/3)); }; %o A372359 A372282sq(n,k) = if(1==n,2*k-1,A371094(A372282sq(n-1,k))); %o A372359 A372359sq(n,k) = A372358(A372282sq(n,k)); %o A372359 A372359list(up_to) = { my(v = vector(up_to), i=0); for(a=1,oo, for(col=1,a, i++; if(i > up_to, return(v)); v[i] = A372359sq((a-(col-1)),col))); (v); }; %o A372359 v372359 = A372359list(up_to); %o A372359 A372359(n) = v372359[n]; %Y A372359 Cf. A003987, A086893, A371094, A372282, A372287, A372354, A372358, A372360 (binary weights). %Y A372359 Cf. also A372353. %K A372359 nonn,tabl %O A372359 1,10 %A A372359 _Antti Karttunen_, May 01 2024