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A318955
Binomial(A319500(n),a(n)) = A006917(n) with 2 <= a(n) <= A319500(n)/2.
2
2, 2, 2, 3, 2, 2, 3, 2, 2, 2, 3, 2, 4, 2, 3, 2, 2, 3, 4, 2, 2, 3, 2, 2, 4, 3, 2, 5, 2, 2, 3, 2, 2, 4, 2, 3, 2, 2, 2, 3, 5, 2, 4, 2, 2, 3, 2, 2, 2, 2, 3, 2, 4, 2, 2, 5, 3, 2, 2, 2, 6, 2, 3, 2, 4, 2, 2, 2, 3, 2, 2, 2, 5, 2, 3, 4, 2, 2, 2, 3, 2, 2, 2, 6, 2, 3, 4, 2, 2, 2, 5, 2, 3, 2, 2, 2, 2, 3, 2
OFFSET
1,1
COMMENTS
First differs from A022912 at n=18.
LINKS
EXAMPLE
a(3) = 6 because A006987(3) = 15 = binomial(6,2).
MAPLE
N:= 10000: # for binomial(n, k) values <= N
S:= {}:
for n from 2 while n*(n-1)/2 <= N do
for k from 2 to n/2 do
v:= binomial(n, k);
if v > N then break fi;
if not member(v, S) then
S:= S union {v};
K[v]:= k;
fi
od od:
A006987:= sort(convert(S, list)):
seq(K[A006987[i]], i=1..nops(A006987));
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert Israel, Sep 20 2018
STATUS
approved