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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.

A341674 Irregular triangle read by rows giving the strictly inferior divisors of n.

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%I A341674 #10 Mar 07 2021 21:02:43
%S A341674 1,1,1,1,1,2,1,1,2,1,1,2,1,1,2,3,1,1,2,1,3,1,2,1,1,2,3,1,1,2,4,1,3,1,
%T A341674 2,1,1,2,3,4,1,1,2,1,3,1,2,4,1,1,2,3,5,1,1,2,4,1,3,1,2,1,5,1,2,3,4,1,
%U A341674 1,2,1,3,1,2,4,5,1,1,2,3,6,1,1,2,4,1,3
%N A341674 Irregular triangle read by rows giving the strictly inferior divisors of n.
%C A341674 We define a divisor d|n to be strictly inferior if d < n/d. The number of strictly inferior divisors of n is A056924(n).
%e A341674 Triangle begins:
%e A341674      1: {}        16: 1,2        31: 1
%e A341674      2: 1         17: 1          32: 1,2,4
%e A341674      3: 1         18: 1,2,3      33: 1,3
%e A341674      4: 1         19: 1          34: 1,2
%e A341674      5: 1         20: 1,2,4      35: 1,5
%e A341674      6: 1,2       21: 1,3        36: 1,2,3,4
%e A341674      7: 1         22: 1,2        37: 1
%e A341674      8: 1,2       23: 1          38: 1,2
%e A341674      9: 1         24: 1,2,3,4    39: 1,3
%e A341674     10: 1,2       25: 1          40: 1,2,4,5
%e A341674     11: 1         26: 1,2        41: 1
%e A341674     12: 1,2,3     27: 1,3        42: 1,2,3,6
%e A341674     13: 1         28: 1,2,4      43: 1
%e A341674     14: 1,2       29: 1          44: 1,2,4
%e A341674     15: 1,3       30: 1,2,3,5    45: 1,3,5
%t A341674 Table[Select[Divisors[n],#<n/#&],{n,100}]
%Y A341674 Initial terms are A000012.
%Y A341674 Row lengths are A056924 (number of strictly inferior divisors).
%Y A341674 Final terms are A060775.
%Y A341674 Row sums are A070039 (sum of strictly inferior divisors).
%Y A341674 The weakly inferior version is A161906.
%Y A341674 The weakly superior version is A161908.
%Y A341674 The odd terms are counted by A333805.
%Y A341674 The prime terms are counted by A333806.
%Y A341674 The squarefree terms are counted by A341596.
%Y A341674 The strictly superior version is A341673.
%Y A341674 The prime-power terms are counted by A341677.
%Y A341674 A001221 counts prime divisors, with sum A001414.
%Y A341674 A001222 counts prime-power divisors.
%Y A341674 A005117 lists squarefree numbers.
%Y A341674 A038548 counts superior (or inferior) divisors.
%Y A341674 A207375 lists central divisors.
%Y A341674 - Inferior: A033676, A063962, A066839, A069288, A217581, A333749, A333750.
%Y A341674 - Superior: A033677, A051283, A059172, A063538, A063539, A070038, A116882, A116883, A341591, A341592, A341593, A341675, A341676.
%Y A341674 - Strictly Superior: A048098, A064052, A140271, A238535, A341594, A341595, A341642, A341643, A341644, A341645, A341646.
%Y A341674 Cf. A000005, A000203, A001055, A001248, A006530, A020639, A050320.
%K A341674 nonn,tabf
%O A341674 1,6
%A A341674 _Gus Wiseman_, Feb 23 2021