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A330587
A(n,k) is the n-th index m such that A330439(m) = k; square array A(n,k), n>=1, k>=1, read by antidiagonals.
4
0, 3, 1, 6, 7, 2, 13, 10, 9, 4, 21, 16, 12, 15, 5, 23, 31, 19, 18, 17, 8, 27, 38, 36, 29, 25, 20, 11, 33, 41, 49, 44, 30, 26, 24, 14, 46, 43, 55, 56, 59, 40, 37, 34, 22, 67, 52, 64, 58, 62, 61, 50, 39, 35, 28, 81, 70, 78, 76, 73, 72, 69, 51, 47, 53, 32, 104, 94, 91, 88, 84, 75, 79, 82, 66, 57, 54, 42
OFFSET
1,2
LINKS
EXAMPLE
Square array A(n,k) begins:
0, 3, 6, 13, 21, 23, 27, 33, 46, 67, ...
1, 7, 10, 16, 31, 38, 41, 43, 52, 70, ...
2, 9, 12, 19, 36, 49, 55, 64, 78, 91, ...
4, 15, 18, 29, 44, 56, 58, 76, 88, 93, ...
5, 17, 25, 30, 59, 62, 73, 84, 90, 98, ...
8, 20, 26, 40, 61, 72, 75, 87, 117, 139, ...
11, 24, 37, 50, 69, 79, 85, 121, 124, 154, ...
14, 34, 39, 51, 82, 102, 118, 142, 155, 157, ...
22, 35, 47, 66, 97, 110, 133, 180, 190, 202, ...
28, 53, 57, 74, 106, 116, 164, 183, 197, 205, ...
MAPLE
b:= proc() 0 end:
g:= proc(n) option remember; local t;
t:= `if`(n<2, n, b(g(n-1))+b(g(n-2)));
b(t):= b(t)+1; t
end:
f:= proc(n) option remember; b(g(n)) end:
A:= proc() local l, t; t, l:= -1, proc() [] end;
proc(n, k) local h;
while nops(l(k))<n do t:= t+1;
h:= f(t); l(h):= [l(h)[], t]
od: l(k)[n]
end
end():
seq(seq(A(n, 1+d-n), n=1..d), d=1..14);
MATHEMATICA
b[_] = 0;
g[n_] := g[n] = Module[{t}, t = If[n < 2, n, b[g[n - 1]] + b[g[n - 2]]]; b[t]++; t];
f[n_] := f[n] = b[g[n]];
A[n_, k_] := Module[{l, t = -1, h}, l[_] = {}; While[Length[l[k]] < n, t++; h = f[t]; AppendTo[l[h], t]]; l[k][[n]]];
Table[Table[A[n, 1 + d - n], {n, 1, d}], {d, 1, 14}] // Flatten (* Jean-François Alcover, Feb 11 2021, after Alois P. Heinz *)
CROSSREFS
Column k=1 gives A330440.
Row n=1 gives A330588.
Main diagonal gives A330589.
Sequence in context: A338995 A359574 A210749 * A350647 A199662 A280293
KEYWORD
nonn,tabl
AUTHOR
Alois P. Heinz, Dec 18 2019
STATUS
approved