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A281302
Largest nonnegative k such that binomial(2*c-1, c-1) == 1 (mod c^k), where c is the n-th composite number.
3
0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
OFFSET
1
COMMENTS
a(n) > 0 if c is either a term of A168363 or a term of A228562.
If c is a term of A267824, then a(n) > 1.
If there is a composite c that is a counterexample to the converse of Wolstenholme's theorem, that composite has a(i) > 2, where i is the index of c in A002808.
LINKS
PROG
(PARI) forcomposite(c=1, , my(k=0); while(Mod(binomial(2*c-1, c-1), c^k)==1, k++); print1(k-1, ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Felix Fröhlich, Jan 21 2017
EXTENSIONS
More terms from Antti Karttunen, Nov 08 2018
STATUS
approved