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 A062851 #5 Oct 14 2023 00:04:40
%S A062851 0,1,3,7,11,18,24,34,45,58,68,85,97,116,136,159,175,201,219,248,277,
%T A062851 308,330,367,400,437,475,517,545,592,622,670,717,766,815,873,909,964,
%U A062851 1020,1083,1123,1189,1231,1298,1366,1433,1479,1557,1623,1700,1774,1854
%N A062851 Number of k such that 1 < k < n X n and k not of the form ij for 1 <= {i, j} <= n.
%C A062851 Smallest k for given n is given by A007918, largest by A005563 (except for some initial terms).
%e A062851 a(4)=7 because there are 9 unique products in the 4 X 4 multiplication table (1 2 3 4 6 8 9 12 16), which excludes 7 non-product integers within the range 1 to 16 (5 7 10 11 13 14 15).
%o A062851 (Python)
%o A062851 def A062851(n): return n**2-len({i*j for i in range(1,n+1) for j in range(1,i+1)}) # _Chai Wah Wu_, Oct 13 2023
%Y A062851 a(n) = n^2 - A027424.
%Y A062851 Cf. A027424, A062854, A062855, A062856, A062857, A062859.
%K A062851 nonn
%O A062851 1,3
%A A062851 Ron A. Lalonde (ronronronlalonde(AT)hotmail.com), Jun 25 2001