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%I #35 Mar 11 2021 15:31:21
%S 1,1,1,3,1,1,5,1,3,1,7,1,1,3,9,1,5,1,11,1,3,1,13,1,7,1,3,5,15,1,1,17,
%T 1,3,9,1,19,1,5,1,3,7,21,1,11,1,23,1,3,1,5,25,1,13,1,3,9,27,1,7,1,29,
%U 1,3,5,15,1,31,1,1,3,11,33,1,17,1,5,7,35,1
%N Triangle read by rows in which row n lists the odd divisors of n.
%C Row lengths: A001227; row sums: A000593; row products: A136655;
%C n-th row = intersection of A005408 and of n-th row of A027750;
%C A000265(n) = T(n,A001227(n)).
%H Reinhard Zumkeller, <a href="/A182469/b182469.txt">Rows n = 1..2500 of triangle, flattened</a>
%F T(n,k) = A027750(A000265(n),k), 1 <= k <= A001227(n).
%e The triangle begins:
%e . 1 {1}
%e . 2 {1}
%e . 3 {1,3}
%e . 4 {1}
%e . 5 {1,5}
%e . 6 {1,3}
%e . 7 {1,7}
%e . 8 {1}
%e . 9 {1,3,9}
%e . 10 {1,5}
%e . 11 {1,11}
%e . 12 {1,3}
%e . 13 {1,13}
%e . 14 {1,7}
%e . 15 {1,3,5,15}
%e . 16 {1} .
%t Flatten[Table[Select[Divisors[n],OddQ],{n,40}]] (* _Harvey P. Dale_, Aug 13 2012 *)
%o (Haskell)
%o a182469 n k = a182469_tabf !! (n-1) !! (k-1)
%o a182469_row = a027750_row . a000265
%o a182469_tabf = map a182469_row [1..]
%o (PARI) tabf(nn) = {for (n=1, nn, fordiv(n, d, if (d%2, print1(d, ", "))); print(););} \\ _Michel Marcus_, Apr 22 2017
%o (Python)
%o from sympy import divisors
%o def row(n):
%o return [d for d in divisors(n) if d % 2]
%o for n in range(1, 21): print(row(n)) # _Indranil Ghosh_, Apr 22 2017
%Y Cf. A027750, A050999, A051000, A037283, A037284, A037285, A171565.
%Y Cf. also A237048.
%K nonn,tabf
%O 1,4
%A _Reinhard Zumkeller_, Apr 30 2012
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