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A254609 Triangle read by rows: T(n,k) = A243757(n)/(A243757(k)*A243757(n-k)). 3

%I #23 Mar 04 2023 04:27:52

%S 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,5,5,5,5,1,1,1,5,5,5,1,1,1,1,1,5,5,1,

%T 1,1,1,1,1,1,5,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,5,5,5,5,1,5,5,5,5,1,1,1,

%U 5,5,5,1,1,5,5,5,1,1,1,1,1,5,5,1,1,1,5,5

%N Triangle read by rows: T(n,k) = A243757(n)/(A243757(k)*A243757(n-k)).

%C These are the generalized binomial coefficients associated with A060904.

%C The exponent of T(n,k) is the number of 'carries' that occur when adding k and n-k in base 5 using the traditional addition algorithm.

%C If T(n,k) != 0 mod 5, then n dominates k in base 5.

%C A194459(n) = number of ones in row n. - _Reinhard Zumkeller_, Feb 04 2015

%H Reinhard Zumkeller, <a href="/A254609/b254609.txt">Rows n = 0..124 of triangle, flattened</a>

%H Tyler Ball, Tom Edgar, and Daniel Juda, <a href="http://dx.doi.org/10.4169/math.mag.87.2.135">Dominance Orders, Generalized Binomial Coefficients, and Kummer's Theorem</a>, Mathematics Magazine, Vol. 87, No. 2, April 2014, pp. 135-143.

%H Tyler Ball and Daniel Juda, <a href="https://scholar.rose-hulman.edu/rhumj/vol14/iss2/2">Dominance over N</a>, Rose-Hulman Undergraduate Mathematics Journal, Vol. 13, No. 2, Fall 2013.

%H Tom Edgar and Michael Z. Spivey, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL19/Edgar/edgar3.html">Multiplicative functions, generalized binomial coefficients, and generalized Catalan numbers</a>, Journal of Integer Sequences, Vol. 19 (2016), Article 16.1.6.

%F T(n,k) = A243757(n)/(A243757(k)*A243757(n-k)).

%F T(n,k) = Product_{i=1..n} A060904(i)/(Product_{i=1..k} A060904(i)*Product_{i=1..n-k} A060904(i)).

%F T(n,k) = A060904(n)/n*(k/A060904(k)*T(n-1,k-1)+(n-k)/A060904(n-k)*T(n-1,k)).

%e The first five terms in A060904 are 1, 1, 1, 1, and 5 and so T(4,2) = 1*1*1*1/((1*1)*(1*1))=1 and T(5,3) = 5*1*1*1*1/((1*1*1)*(1*1))=5.

%e The triangle begins:

%e 1

%e 1, 1

%e 1, 1, 1

%e 1, 1, 1, 1

%e 1, 1, 1, 1, 1

%e 1, 5, 5, 5, 5, 1

%e 1, 1, 5, 5, 5, 1, 1

%e 1, 1, 1, 5, 5, 1, 1, 1

%e 1, 1, 1, 1, 5, 1, 1, 1, 1

%e 1, 1, 1, 1, 1, 1, 1, 1, 1, 1

%e 1, 5, 5, 5, 5, 1, 5, 5, 5, 5, 1

%e 1, 1, 5, 5, 5, 1, 1, 5, 5, 5, 1, 1

%e 1, 1, 1, 5, 5, 1, 1, 1, 5, 5, 1, 1, 1

%e 1, 1, 1, 1, 5, 1, 1, 1, 1, 5, 1, 1, 1, 1

%e 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1

%o P=[0]+[5^valuation(i,5) for i in [1..100]]

%o [m for sublist in [[mul(P[1:n+1])/(mul(P[1:k+1])*mul(P[1:(n-k)+1])) for k in [0..n]] for n in [0..len(P)-1]] for m in sublist]

%o (Haskell)

%o import Data.List (inits)

%o a254609 n k = a254609_tabl !! n !! k

%o a254609_row n = a254609_tabl !! n

%o a254609_tabl = zipWith (map . div)

%o a243757_list $ zipWith (zipWith (*)) xss $ map reverse xss

%o where xss = tail $ inits a243757_list

%o -- _Reinhard Zumkeller_, Feb 04 2015

%Y Cf. A060904, A243757, A234957, A242849, A082907.

%Y Cf. A194459.

%K nonn,tabl

%O 0,17

%A _Tom Edgar_, Feb 02 2015

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Last modified April 19 17:39 EDT 2024. Contains 371797 sequences. (Running on oeis4.)