

A057607


Triangle T(n,k) = number of binary ntuples u having exactly k grandchildren, where a grandchild is a vector obtained by deleting any two coordinates of u (n >= 2, 0<=k<=2^(n2)).


2



4, 0, 2, 6, 0, 2, 4, 6, 4, 0, 2, 4, 8, 4, 8, 4, 2, 0, 0, 2, 4, 10, 6, 12, 8, 8, 6, 6, 0, 2, 0, 0, 0, 0, 0, 0, 2, 4, 12, 8, 16, 14, 16, 12, 12, 12, 6, 4, 8, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 14, 10, 20, 22, 24, 22, 22, 26, 18, 16, 12, 16, 12, 0, 4, 10, 0
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OFFSET

2,1


COMMENTS



REFERENCES

N. J. A. Sloane, On singledeletioncorrecting codes, in Codes and Designs (Columbus, OH, 2000), 273291, Ohio State Univ. Math. Res. Inst. Publ., 10, de Gruyter, Berlin, 2002.


LINKS



EXAMPLE

Triangle begins:
4;
0,2,6;
0,2,4,6,4;
0,2,4,8,4,8,4,2,0;
...
a(2)=4 because each of 00, 01, 10, 11, leaves no grandchildren.  Sean A. Irvine, Jun 20 2022


PROG

(Haskell)
a057607 n k = a057607_tabf !! (n2) !! k
a057607_row n = a057607_tabf !! (n2)
a057607_tabf = [4] : map (0 :) a057606_tabf


CROSSREFS



KEYWORD

nonn,tabf,nice


AUTHOR



EXTENSIONS



STATUS

approved



