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A174382 T(1,0)=0 and for n > 1, T(n,k) is the number of k's in rows 1 to n - 1. 4

%I #22 Oct 11 2022 11:11:31

%S 0,1,1,1,1,3,1,4,0,1,2,6,0,1,1,3,8,1,1,1,0,1,4,12,1,2,1,0,1,0,1,6,16,

%T 2,2,2,0,1,0,1,0,0,0,1,11,19,5,2,2,0,2,0,1,0,0,0,1,0,0,0,1,19,22,8,2,

%U 2,1,2,0,1,0,0,1,1,0,0,0,1,0,0,1,27,28,11,2,2,1,2,0,2,0,0,1,1,0,0,0,1,0,0,2

%N T(1,0)=0 and for n > 1, T(n,k) is the number of k's in rows 1 to n - 1.

%C Construction as in A333867 but starting with a 0 and including a count of 0s at the start of each row. [Edited by _Peter Munn_, Oct 11 2022]

%C See A342585 for a similarly defined sequence that has been analyzed more and has lists of other related sequences. - _Peter Munn_, Oct 08 2022

%H Reinhard Zumkeller, <a href="/A174382/b174382.txt">Rows n = 1..25 of table, flattened</a>

%e 0;

%e 1; # one zero

%e 1,1; # one zero, one one

%e 1,3; # one zero, three ones

%e 1,4,0,1; # one zero, four ones, zero twos, one three

%o (Haskell)

%o import Data.List (sort, group)

%o a174382 n k = a174382_tabf !! (n-1) !! k

%o a174382_row n = a174382_tabf !! (n-1)

%o a174382_tabf = iterate f [0] where

%o f xs = g (xs ++ [0, 0 ..]) [0..] (map head zs) (map length zs)

%o where g _ _ _ [] = []

%o g (u:us) (k:ks) hs'@(h:hs) vs'@(v:vs)

%o | k == h = u + v : g us ks hs vs

%o | k /= h = u : g us ks hs' vs'

%o zs = group $ sort xs

%o -- _Reinhard Zumkeller_, Apr 06 2014

%Y Cf. A240508 (row lengths).

%Y Cf. A333867, A342585.

%K easy,nonn,tabf,look

%O 1,6

%A _Paolo P. Lava_ & _Giorgio Balzarotti_, Mar 17 2010

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Last modified August 3 08:07 EDT 2024. Contains 374885 sequences. (Running on oeis4.)