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 A211805 Rectangular array:  R(k,n) = number of ordered triples (w,x,y) with all terms in {1,...,n} and 2w^k>=x^k+y
 1, 5, 1, 16, 5, 1, 36, 14, 5, 1, 69, 32, 14, 5, 1, 117, 61, 30, 14, 5, 1, 184, 103, 57, 30, 14, 5, 1, 272, 162, 99, 55, 30, 14, 5, 1, 385, 240, 156, 91, 55, 30, 14, 5, 1, 525, 341, 230, 146, 91, 55, 30, 14, 5, 1, 696, 465, 323, 220, 140, 91, 55, 30, 14, 5, 1, 900 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row 1:  A055232 Row 2:  A211803 Row 3:  A211804 Limiting row sequence: A000330 Let R be the array in A211802 and let R' be the array in A211805.  Then R(k,n)+R'(k,n)=3^(n-1). See the Comments at A211790. LINKS EXAMPLE Northwest corner: 1...5...16...36...69...117...184 1...5...14...32...61...103...162 1...5...14...30...57...99....156 1...5...14...30...55...91....146 1...5...14...30...55...91....140 MATHEMATICA z = 48; t[k_, n_] := Module[{s = 0},    (Do[If[2 w^k >= x^k + y^k, s = s + 1],        {w, 1, #}, {x, 1, #}, {y, 1, #}] &[n]; s)]; Table[t[1, n], {n, 1, z}]  (* A055232 *) Table[t[2, n], {n, 1, z}]  (* A211803 *) Table[t[3, n], {n, 1, z}]  (* A211804 *) TableForm[Table[t[k, n], {k, 1, 12}, {n, 1, 16}]] Flatten[Table[t[k, n - k + 1], {n, 1, 12},                {k, 1, n}]] (* A211805 *) Table[k (k + 1) (2 k + 1)/6,     {k, 1, z}] (* row-limit sequence, A000330 *) (* Peter J. C. Moses, Apr 13 2012 *) CROSSREFS Cf. A211790. Sequence in context: A283434 A019429 A221364 * A211808 A093826 A144699 Adjacent sequences:  A211802 A211803 A211804 * A211806 A211807 A211808 KEYWORD nonn,tabl AUTHOR Clark Kimberling, Apr 22 2012 STATUS approved

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Last modified March 28 19:41 EDT 2020. Contains 333103 sequences. (Running on oeis4.)