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 A371103 #9 Apr 21 2024 14:29:15
%S A371103 1,1,2,1,3,3,1,3,3,4,1,1,1,6,5,1,1,1,9,2,6,1,1,1,1,3,9,7,1,1,1,1,3,1,
%T A371103 6,8,1,1,1,1,1,1,8,12,9,1,1,1,1,1,1,12,18,1,10,1,1,1,1,1,1,18,27,1,15,
%U A371103 11,1,1,1,1,1,1,27,21,1,12,9,12,1,1,1,1,1,1,21,16,1,17,7,18,13,1,1,1,1,1,1,16,23,1,4,2,27,5,14
%N A371103 Array A read by upward antidiagonals in which the entry A(n,k) in row n and column k is defined by A(n, k) = A371092(A371102(n, k)), n,k >= 1.
%C A371103 A(n, k) gives the column index of A371102(n, k) in array A257852.
%e A371103 Array begins:
%e A371103 n\k| 1 2 3 ...
%e A371103 ---+--------------------------------------------------------------------
%e A371103 1 | 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
%e A371103 2 | 1, 3, 3, 6, 2, 9, 6, 12, 1, 15, 9, 18, 5, 21, 12, 24, 4,
%e A371103 3 | 1, 3, 1, 9, 3, 1, 8, 18, 1, 12, 7, 27, 2, 8, 17, 36, 5,
%e A371103 4 | 1, 1, 1, 1, 3, 1, 12, 27, 1, 17, 2, 21, 3, 12, 4, 54, 2,
%e A371103 5 | 1, 1, 1, 1, 1, 1, 18, 21, 1, 4, 2, 16, 3, 18, 5, 81, 3,
%e A371103 6 | 1, 1, 1, 1, 1, 1, 27, 16, 1, 5, 3, 23, 1, 27, 2, 16, 3,
%e A371103 7 | 1, 1, 1, 1, 1, 1, 21, 23, 1, 2, 3, 18, 1, 21, 3, 23, 1,
%e A371103 8 | 1, 1, 1, 1, 1, 1, 16, 18, 1, 3, 1, 26, 1, 16, 3, 18, 1,
%e A371103 9 | 1, 1, 1, 1, 1, 1, 23, 26, 1, 3, 1, 39, 1, 23, 1, 26, 1,
%e A371103 10 | 1, 1, 1, 1, 1, 1, 18, 39, 1, 1, 1, 30, 1, 18, 1, 39, 1,
%e A371103 11 | 1, 1, 1, 1, 1, 1, 26, 30, 1, 1, 1, 44, 1, 26, 1, 30, 1,
%e A371103 12 | 1, 1, 1, 1, 1, 1, 39, 44, 1, 1, 1, 66, 1, 39, 1, 44, 1,
%e A371103 13 | 1, 1, 1, 1, 1, 1, 30, 66, 1, 1, 1, 99, 1, 30, 1, 66, 1,
%e A371103 14 | 1, 1, 1, 1, 1, 1, 44, 99, 1, 1, 1, 75, 1, 44, 1, 99, 1,
%e A371103 15 | 1, 1, 1, 1, 1, 1, 66, 75, 1, 1, 1, 28, 1, 66, 1, 75, 1,
%e A371103 16 | 1, 1, 1, 1, 1, 1, 99, 28, 1, 1, 1, 42, 1, 99, 1, 28, 1,
%e A371103 17 | 1, 1, 1, 1, 1, 1, 75, 42, 1, 1, 1, 63, 1, 75, 1, 42, 1,
%e A371103 18 | 1, 1, 1, 1, 1, 1, 28, 63, 1, 1, 1, 48, 1, 28, 1, 63, 1,
%e A371103 19 | 1, 1, 1, 1, 1, 1, 42, 48, 1, 1, 1, 71, 1, 42, 1, 48, 1,
%e A371103 20 | 1, 1, 1, 1, 1, 1, 63, 71, 1, 1, 1, 54, 1, 63, 1, 71, 1,
%e A371103 21 | 1, 1, 1, 1, 1, 1, 48, 54, 1, 1, 1, 80, 1, 48, 1, 54, 1,
%o A371103 (PARI)
%o A371103 up_to = 105;
%o A371103 A000265(n) = (n>>valuation(n,2));
%o A371103 A371092(n) = floor((A000265(1+(3*n))+5)/6);
%o A371103 A371094(n) = { my(m=1+3*n, e=valuation(m,2)); ((m*(2^e)) + (((4^e)-1)/3)); };
%o A371103 A371102sq(n,k) = if(1==n,4*k-1,A371094(A371102sq(n-1,k)));
%o A371103 A371103sq(n,k) = A371092(A371102sq(n,k));
%o A371103 A371103list(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] = A371103sq((a-(col-1)),col))); (v); };
%o A371103 v371103 = A371103list(up_to);
%o A371103 A371103(n) = v371103[n];
%Y A371103 Cf. A000027 (row 1), A257852, A371092, A371102.
%Y A371103 Cf. also arrays A371097, A371101.
%K A371103 nonn,tabl,easy
%O A371103 1,3
%A A371103 _Antti Karttunen_, Apr 21 2024