A257807 a(n) = number of odd numbers in range 0 .. n of A233271, the infinite trunk of inverted binary beanstalk.

0, 1, 1, 1, 2, 2, 2, 3, 3, 4, 4, 4, 5, 5, 5, 5, 5, 6, 7, 7, 7, 8, 8, 9, 10, 11, 11, 12, 12, 12, 13, 13, 13, 13, 14, 15, 15, 15, 16, 16, 16, 17, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 20, 21, 22, 23, 23, 24, 24, 24, 25, 25, 25, 25, 26, 27, 27, 27, 28, 28, 29, 29, 29, 30, 31, 32, 33, 34, 34, 34, 34, 35, 36, 37, 37, 37, 37, 37, 37, 37, 38

Offset

0,5

Comments

a(0) = 0; and for n >= 1: a(n) = the largest number k such that A257803(k) <= n.

Links

Antti Karttunen, Table of n, a(n) for n = 0..16405

Formula

a(0) = 0; for n >= 1, a(n) = A257800(n) + a(n-1).

Other identities:

For all n >= 0, a(n) = A257808(n) - A257806(n).

For all n >= 1, a(A257803(n)) = n. [This sequence works as a left inverse of injection A257803.]

Prog

(Scheme, with memoization-macro definec)
(definec (A257807 n) (if (zero? n) n (+ (A257800 n) (A257807 (- n 1)))))

Crossrefs

Partial sums of A257800.

Cf. A233271, A257803, A257806, A257808.

Sequence in context: A302931 A227145 A039730 * A152595 A176844 A085182

Adjacent sequences: A257804 A257805 A257806 * A257808 A257809 A257810

Keyword

nonn

Author

Antti Karttunen, May 12 2015

Status

approved