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A259600
Triangular array: sums of two distinct lower Wythoff numbers.
5
4, 5, 7, 7, 9, 10, 9, 11, 12, 14, 10, 12, 13, 15, 17, 12, 14, 15, 17, 19, 20, 13, 15, 16, 18, 20, 21, 23, 15, 17, 18, 20, 22, 23, 25, 26, 17, 19, 20, 22, 24, 25, 27, 28, 30, 18, 20, 21, 23, 25, 26, 28, 29, 31, 33, 20, 22, 23, 25, 27, 28, 30, 31, 33, 35, 36
OFFSET
2,1
COMMENTS
Row n shows the numbers u(m) + u(n), where u = A000201 (lower Wythoff sequence), for m=1..n-1, for n >= 2. (The offset is 2, so that the top row is counted as row 2.)
EXAMPLE
10 = 4 + 6 = u(3) + u(4), so that 10 appears as the final term in row 4. (The offset is 2, so that the top row is counted as row 2.) Rows 2 to 9:
4
5 7
7 9 10
9 11 12 14
10 12 13 15 17
12 14 15 17 19 20
13 15 16 18 20 21 23
15 17 18 20 22 23 25 26
MATHEMATICA
r = GoldenRatio; z = 20; u[n_] := u[n] = Floor[n*r];
s[m_, n_] := u[m] + u[n]; t = Table[s[m, n], {n, 2, z}, {m, 1, n - 1}];
TableForm[t] (* A259600 array *)
Flatten[t] (* A259600 sequence *)
PROG
(PARI) tabl(nn) = {r=(sqrt(5)+1)/2; for (n=2, nn, for (k=1, n-1, print1(floor(n*r) + floor(k*r), ", "); ); print(); ); } \\ Michel Marcus, Jul 30 2015
CROSSREFS
Sequence in context: A004221 A239504 A033557 * A088298 A075992 A022294
KEYWORD
nonn,tabl,easy
AUTHOR
Clark Kimberling, Jul 22 2015
STATUS
approved