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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.

A372356 Array read by upward antidiagonals: A(n, k) = A372354(1+n,k)-A372354(n,k), n,k >= 1.

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%I A372356 #5 Apr 30 2024 17:05:23
%S A372356 4,8,3,16,8,6,32,16,12,3,64,32,24,5,3,128,64,48,9,7,3,256,128,96,21,
%T A372356 13,5,5,512,256,192,44,25,13,12,3,1024,512,384,88,53,28,24,5,3,2048,
%U A372356 1024,768,176,108,56,48,8,9,2,4096,2048,1536,352,216,112,96,21,20,7,8,8192,4096,3072,704,432,224,192,44,40,13,16,3
%N A372356 Array read by upward antidiagonals: A(n, k) = A372354(1+n,k)-A372354(n,k), n,k >= 1.
%e A372356 Array begins:
%e A372356 n\k|    1     2     3    4    5    6     7    8     9   10    11   12   13   14
%e A372356 ---+-----------------------------------------------------------------------------
%e A372356 1  |    4,    3,    6,   3,   3,   3,    5,   3,    3,   2,    8,   3,   4,   3,
%e A372356 2  |    8,    8,   12,   5,   7,   5,   12,   5,    9,   7,   16,   4,   6,   5,
%e A372356 3  |   16,   16,   24,   9,  13,  13,   24,   8,   20,  13,   32,  13,  15,  11,
%e A372356 4  |   32,   32,   48,  21,  25,  28,   48,  21,   40,  25,   64,  28,  29,  21,
%e A372356 5  |   64,   64,   96,  44,  53,  56,   96,  44,   80,  53,  128,  56,  57,  40,
%e A372356 6  |  128,  128,  192,  88, 108, 112,  192,  88,  160, 108,  256, 112, 117,  81,
%e A372356 7  |  256,  256,  384, 176, 216, 224,  384, 176,  320, 216,  512, 224, 236, 161,
%e A372356 8  |  512,  512,  768, 352, 432, 448,  768, 352,  640, 432, 1024, 448, 472, 324,
%e A372356 9  | 1024, 1024, 1536, 704, 864, 896, 1536, 704, 1280, 864, 2048, 896, 944, 647,
%o A372356 (PARI)
%o A372356 up_to = 78;
%o A372356 A000523(n) = logint(n,2);
%o A372356 A371094(n) = { my(m=1+3*n, e=valuation(m,2)); ((m*(2^e)) + (((4^e)-1)/3)); };
%o A372356 A372282sq(n,k) = if(1==n,2*k-1,A371094(A372282sq(n-1,k)));
%o A372356 A372356sq(n,k) = { my(x=A372282sq(n,k)); (A000523(A371094(x))-A000523(x)); };
%o A372356 A372356list(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] = A372356sq((a-(col-1)),col))); (v); };
%o A372356 v372356 = A372356list(up_to);
%o A372356 A372356(n) = v372356[n];
%Y A372356 Columnwise first differences of A372354.
%Y A372356 Cf. A000523, A371094, A372282, A372357.
%K A372356 nonn,tabl
%O A372356 1,1
%A A372356 _Antti Karttunen_, Apr 30 2024