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A082406 Numbers k such that k divides Sum_{j=1..k} binomial(2j,j). 1
1, 2, 5, 8, 11, 12, 17, 23, 29, 41, 47, 53, 59, 71, 83, 89, 101, 107, 113, 130, 131, 137, 149, 167, 173, 179, 191, 196, 197, 227, 233, 238, 239, 251, 257, 263, 266, 269, 281, 293, 311, 317, 322, 347, 353, 359, 383, 389, 401, 419, 431, 443, 449, 461, 467, 479 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
Is a(n) asymptotic to c*n*log(n) with 2 < c < 2.3?
MATHEMATICA
Select[Range[500], Divisible[Sum[Binomial[2k, k], {k, #}], #]&] (* Harvey P. Dale, Feb 16 2013 *)
A066796 = Accumulate[Table[Binomial[2*k, k], {k, 1, 1000}]]; Select[Range[Length[A066796]], Divisible[A066796[[#]], #] &] (* Vaclav Kotesovec, Feb 15 2019 *)
CROSSREFS
Cf. A066796.
Sequence in context: A083422 A187581 A167409 * A215938 A352748 A007826
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Apr 23 2003
STATUS
approved

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Last modified March 28 15:38 EDT 2024. Contains 371254 sequences. (Running on oeis4.)