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A137240
Number of nonnegative k such that binomial(k, floor(k/2)) has n decimal digits.
1
5, 4, 4, 3, 4, 3, 3, 4, 3, 4, 3, 3, 4, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3, 3, 4, 3
OFFSET
1,1
COMMENTS
Equivalently the number of terms of A001405 with n digits.
LINKS
EXAMPLE
a(1) = 5 because there are 5 terms of A001405 with 1 digit : 1, 1, 2, 3, 6.
PROG
(PARI) seq(n)={my(v=vector(n), k=0, t=1); while(t<=#v, v[t]++; k++; t=1+logint(binomial(k, k\2), 10)); v} \\ Andrew Howroyd, Feb 03 2020
CROSSREFS
Cf. A001405.
Sequence in context: A220248 A147533 A241183 * A243380 A244999 A201129
KEYWORD
easy,nonn,base
AUTHOR
Ctibor O. Zizka, Mar 09 2008
EXTENSIONS
Name clarified and terms a(58) and beyond from Andrew Howroyd, Feb 03 2020
STATUS
approved