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%I #33 Mar 14 2021 01:03:38
%S 1,1,1,2,1,1,2,1,1,2,1,3,1,2,1,1,3,2,1,1,2,1,3,1,4,2,1,1,3,2,1,1,4,2,
%T 1,3,1,2,1,1,4,3,2,1,5,1,2,1,3,1,4,2,1,1,5,3,2,1,1,4,2,1,3,1,2,1,5,1,
%U 6,4,3,2,1,1,2,1,3,1,5,4,2,1,1,6,3,2,1
%N Irregular triangle read by rows in which row n lists the positive divisors of n that are <= sqrt(n) in decreasing order.
%C Reversing rows gives A161906.
%F a(n) * A161908(n) = A340792(n)
%F A161906(n) * A340791(n) = A340792(n)
%F A027750(n) * A056538(n) = A061017(n)
%e Triangle begins:
%e 1
%e 1
%e 1
%e 2 1
%e 1
%e 2 1
%e 1
%e 2 1
%e 3 1
%e 2 1
%e 1
%e 3 2 1
%e 1
%e 2 1
%e 3 1
%e 4 2 1
%o (PARI) row(n) = Vecrev(select(x->(x<=sqrt(n)), divisors(n))); \\ _Jinyuan Wang_, Mar 13 2021
%Y Cf. A038548 (row widths), A033676 (first column), A333750 (second column), A161906 (rows reversed), A027750, A056538, A061017, A340791, A340792.
%K nonn,tabf
%O 1,4
%A _Charles Kusniec_, Feb 27 2021
%E More terms from _Jinyuan Wang_, Mar 13 2021
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