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A100869 Triangle read by rows: T(n,k) = minimal sum of denominators needed to write k/n (for 1 <= k <= n with gcd(k,n) = 1) as a sum of unit fractions, where k/n is in lowest terms. 2

%I

%S 2,3,8,4,6,5,18,12,17,6,5,7,32,39,16,23,36,8,12,10,14,9,24,12,20,17,

%T 23,10,15,7,20,11,72,48,36,47,24,35,95,72,60,12,10,7,12,13,98,71,82,

%U 95,101,28,41,47,58,71,96,14,21,34,9,34,41,15,32,16,21,8,23,13,15,16,24,20,28

%N Triangle read by rows: T(n,k) = minimal sum of denominators needed to write k/n (for 1 <= k <= n with gcd(k,n) = 1) as a sum of unit fractions, where k/n is in lowest terms.

%H <a href="/index/Ed#Egypt">Index entries for sequences related to Egyptian fractions</a>

%e The table starts:

%e 2

%e 3 8

%e 4 6

%e 5 18 12 17

%e T(5,2) = 18 because the minimal sum of unit fractions is 2/5 = 1/3 + 1/15 and 3+15=18.

%Y Cf. A100870, A100871.

%K nonn,tabf

%O 1,1

%A _Franklin T. Adams-Watters_, Nov 20 2004

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Last modified December 2 20:25 EST 2021. Contains 349445 sequences. (Running on oeis4.)