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A022414
Kim-sums: "Kimberling sums" K_n + K_3.
4
2, 7, 10, 4, 15, 18, 20, 23, 9, 28, 31, 12, 36, 39, 41, 44, 17, 49, 52, 54, 57, 22, 62, 65, 25, 70, 73, 75, 78, 30, 83, 86, 33, 91, 94, 96, 99, 38, 104, 107, 109, 112, 43, 117, 120, 46, 125, 128, 130, 133, 51, 138, 141, 143, 146, 56, 151, 154, 59, 159, 162, 164, 167
OFFSET
0,1
COMMENTS
Let W(i,j) denote the index of that row of the extended Wythoff array (see A035513) that contains the sequence formed by the sum of rows i and j. Then a(n) = W(2,n). - N. J. A. Sloane, Mar 07 2016
REFERENCES
J. H. Conway, Posting to Math Fun Mailing List, Dec 02 1996.
M. LeBrun, Posting to Math Fun Mailing List Jan 10 1997.
LINKS
J. H. Conway, Allan Wechsler, Marc LeBrun, Dan Hoey, and N. J. A. Sloane, On Kimberling Sums and Para-Fibonacci Sequences, Correspondence and Postings to Math-Fun Mailing List, Nov 1996 to Jan 1997
MAPLE
Ki := proc(n, i)
option remember;
local phi ;
phi := (1+sqrt(5))/2 ;
if i= 0 then
n;
elif i=1 then
floor((n+1)*phi) ;
else
procname(n, i-1)+procname(n, i-2) ;
end if;
end proc:
Kisum := proc(n, m)
local ks, a, i;
ks := [seq( Ki(n, i)+Ki(m, i), i=0..5)] ;
for i from 0 to 2 do
for a from 0 do
if Ki(a, 0) = ks[i+1] and Ki(a, 1) = ks[i+2] then
return a;
end if;
if Ki(a, 0) > ks[i+1] then
break;
end if;
end do:
end do:
end proc:
A022414 := proc(n)
if n = 0 then
2;
else
Kisum(n-1, 2) ;
end if;
end proc:
seq(A022414(i), i=0..80) ; # R. J. Mathar, Sep 03 2016
MATHEMATICA
Ki[n_, i_] := Ki[n, i] = Which[i == 0, n, i == 1, Floor[(n + 1)* GoldenRatio], True, Ki[n, i - 1] + Ki[n, i - 2]];
Kisum [n_, m_] := Module[{ks, a, i}, ks = Table[Ki[n, i] + Ki[m, i], {i, 0, 5}]; For[i = 0, i <= 2, i++, For[a = 0, True, a++, If[Ki[a, 0] == ks[[i + 1]] && Ki[a, 1] == ks[[i + 2]], Return@a]; If[Ki[a, 0] > ks[[i + 1]], Break[]]]]];
a[n_] := If[n == 0, 2, Kisum[n - 1, 2]];
Table[a[n], {n, 0, 80}] (* Jean-François Alcover, Oct 15 2023, after R. J. Mathar *)
CROSSREFS
The "Kim-sums" K_n + K_i for i = 2 through 12 are given in A022413, A022414, A022415, A022416, ..., A022423.
Sequence in context: A041453 A042157 A012937 * A319932 A236243 A024831
KEYWORD
nonn,easy
AUTHOR
STATUS
approved