A260910 Triangle read by rows: Fresenius numbers of n and A077664(n,k), k = 1..n.
-1, 1, 3, 5, 7, 11, 11, 17, 23, 29, 19, 23, 27, 31, 39, 29, 49, 59, 79, 89, 109, 41, 47, 53, 59, 65, 71, 83, 55, 69, 83, 97, 111, 125, 139, 153, 71, 79, 95, 103, 119, 127, 143, 151, 167, 89, 107, 143, 161, 179, 197, 233, 251, 269, 287, 109, 119, 129, 139
Offset: 1
Examples
. 1: -1 . 2: 1 3 . 3: 5 7 11 . 4: 11 17 23 29 . 5: 19 23 27 31 39 . 6: 29 49 59 79 89 109 . 7: 41 47 53 59 65 71 83 . 8: 55 69 83 97 111 125 139 153 . 9: 71 79 95 103 119 127 143 151 167 . 10: 89 107 143 161 179 197 233 251 269 287 . 11: 109 119 129 139 149 159 169 179 189 199 219 . 12: 131 175 197 241 263 307 329 373 395 439 461 505 .
Links
- Reinhard Zumkeller, Rows n = 1..125 of triangle, flattened
- Eric Weisstein's World of Mathematics, Frobenius Number.
- Wikipedia, Coin problem
Programs
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Haskell
a260910 n k = a260910_tabl !! (n - 1) !! (k-1) a260910_row n = a260910_tabl !! (n-1) a260910_tabl = zipWith (map . sylvester) [1..] a077664_tabl where sylvester u v = u * v - u - v
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Mathematica
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[n_, k_] := (n-1) row[n][[k]] - n; Table[T[n, k], {n, 1, 12}, {k, 1, n}] // Flatten (* Jean-François Alcover, Sep 21 2021 *)
Formula
T(n,k) = (n-1) * A077664(n,k) - n.
Comments