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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.

A351962 Square array A(n,k) = A156552(lcm(A005940(1+n), A005940(1+k))), read by antidiagonals.

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%I A351962 #7 Feb 27 2022 22:56:23
%S A351962 0,1,1,2,1,2,3,5,5,3,4,3,2,3,4,5,9,11,11,9,5,6,5,10,3,10,5,6,7,13,5,
%T A351962 19,19,5,13,7,8,7,6,11,4,11,6,7,8,9,17,23,27,21,21,27,23,17,9,10,9,18,
%U A351962 7,22,5,22,7,18,9,10,11,21,21,35,39,13,13,39,35,21,21,11,12,11,10,19,20,23,6,23,20,19,10,11,12
%N A351962 Square array A(n,k) = A156552(lcm(A005940(1+n), A005940(1+k))), read by antidiagonals.
%C A351962 The indices run as A(0,0), A(0,1), A(1,0), A(0,2), A(1,1), A(2,0), etc. The array is symmetric.
%H A351962 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H A351962 <a href="/index/Lc#lcm">Index entries for sequences related to lcm's</a>
%e A351962 The top left corner of the array:
%e A351962       n=0   1   2   3   4   5    6    7    8   9   10   11   12
%e A351962 -----|-----------------------------------------------------------
%e A351962 k= 0 |  0,  1,  2,  3,  4,  5,   6,   7,   8,  9,  10,  11,  12,
%e A351962    1 |  1,  1,  5,  3,  9,  5,  13,   7,  17,  9,  21,  11,  25,
%e A351962    2 |  2,  5,  2, 11, 10,  5,   6,  23,  18, 21,  10,  11,  26,
%e A351962    3 |  3,  3, 11,  3, 19, 11,  27,   7,  35, 19,  43,  11,  51,
%e A351962    4 |  4,  9, 10, 19,  4, 21,  22,  39,  20,  9,  10,  43,  12,
%e A351962    5 |  5,  5,  5, 11, 21,  5,  13,  23,  37, 21,  21,  11,  53,
%e A351962    6 |  6, 13,  6, 27, 22, 13,   6,  55,  38, 45,  22,  27,  54,
%e A351962    7 |  7,  7, 23,  7, 39, 23,  55,   7,  71, 39,  87,  23, 103,
%e A351962    8 |  8, 17, 18, 35, 20, 37,  38,  71,   8, 41,  42,  75,  44,
%e A351962    9 |  9,  9, 21, 19,  9, 21,  45,  39,  41,  9,  21,  43,  25,
%e A351962   10 | 10, 21, 10, 43, 10, 21,  22,  87,  42, 21,  10,  43,  26,
%e A351962   11 | 11, 11, 11, 11, 43, 11,  27,  23,  75, 43,  43,  11, 107,
%e A351962   12 | 12, 25, 26, 51, 12, 53,  54, 103,  44, 25,  26, 107,  12,
%e A351962   13 | 13, 13, 13, 27, 45, 13,  13,  55,  77, 45,  45,  27, 109,
%e A351962   14 | 14, 29, 14, 59, 46, 29,  14, 119,  78, 93,  46,  59, 110,
%e A351962   15 | 15, 15, 47, 15, 79, 47, 111,  15, 143, 79, 175,  47, 207,
%e A351962   16 | 16, 33, 34, 67, 36, 69,  70, 135,  40, 73,  74, 139,  76,
%o A351962 (PARI)
%o A351962 up_to = 104;
%o A351962 A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); (t); };
%o A351962 A156552(n) = { my(f = factor(n), p, p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res };
%o A351962 A351962sq(n,k) = A156552(lcm(A005940(1+n),A005940(1+k)));
%o A351962 A351962list(up_to) = { my(v = vector(1+up_to), i=0); for(a=0,oo, for(col=0,a, i++; if(i > #v, return(v)); v[i] = A351962sq(col,(a-(col))))); (v); };
%o A351962 v351962 = A351962list(up_to);
%o A351962 A351962(n) = v351962[1+n];
%Y A351962 Cf. A003990, A005940, A156552.
%Y A351962 Cf. A001477 (main diagonal).
%Y A351962 Cf. also A341520, A351960, A351961.
%K A351962 nonn,tabl
%O A351962 0,4
%A A351962 _Antti Karttunen_, Feb 26 2022