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Triangle read by rows: Fresenius numbers of n and A077664(n,k), k = 1..n.
3

%I #8 Sep 21 2021 09:50:17

%S -1,1,3,5,7,11,11,17,23,29,19,23,27,31,39,29,49,59,79,89,109,41,47,53,

%T 59,65,71,83,55,69,83,97,111,125,139,153,71,79,95,103,119,127,143,151,

%U 167,89,107,143,161,179,197,233,251,269,287,109,119,129,139

%N Triangle read by rows: Fresenius numbers of n and A077664(n,k), k = 1..n.

%C For n > 1: T(n,1) = A028387(n-2).

%H Reinhard Zumkeller, <a href="/A260910/b260910.txt">Rows n = 1..125 of triangle, flattened</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/FrobeniusNumber.html">Frobenius Number</a>.

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Coin_problem">Coin problem</a>

%F T(n,k) = (n-1) * A077664(n,k) - n.

%e . 1: -1

%e . 2: 1 3

%e . 3: 5 7 11

%e . 4: 11 17 23 29

%e . 5: 19 23 27 31 39

%e . 6: 29 49 59 79 89 109

%e . 7: 41 47 53 59 65 71 83

%e . 8: 55 69 83 97 111 125 139 153

%e . 9: 71 79 95 103 119 127 143 151 167

%e . 10: 89 107 143 161 179 197 233 251 269 287

%e . 11: 109 119 129 139 149 159 169 179 189 199 219

%e . 12: 131 175 197 241 263 307 329 373 395 439 461 505 .

%t row[n_] := Module[{j, k}, Reap[For[j = n+1; k = 1, k <= n, j++, If[CoprimeQ[n, j], Sow[j]; k++]]][[2, 1]]];

%t T[n_, k_] := (n-1) row[n][[k]] - n;

%t Table[T[n, k], {n, 1, 12}, {k, 1, n}] // Flatten (* _Jean-François Alcover_, Sep 21 2021 *)

%o (Haskell)

%o a260910 n k = a260910_tabl !! (n - 1) !! (k-1)

%o a260910_row n = a260910_tabl !! (n-1)

%o a260910_tabl = zipWith (map . sylvester) [1..] a077664_tabl where

%o sylvester u v = u * v - u - v

%Y Cf. A077664, A028387.

%K sign,tabl

%O 1,3

%A _Reinhard Zumkeller_, Aug 04 2015