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A257509 Numbers n for which A257265(n) = 2; numbers for which the nearest descendant leaf in the binary beanstalk is two edges away. 5
0, 8, 16, 19, 32, 35, 42, 53, 64, 67, 74, 85, 89, 101, 109, 112, 128, 131, 138, 149, 153, 165, 173, 176, 184, 197, 205, 208, 221, 224, 231, 240, 256, 259, 266, 277, 281, 293, 301, 304, 312, 325, 333, 336, 349, 352, 359, 368, 375, 389, 397, 400, 413, 416, 423, 432, 445, 448, 455, 464, 470, 480, 487, 492, 512 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Numbers n for which A257265(n) = 2.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16385

Paul Tek, Illustration of how natural numbers in range 0 .. 133 are organized as a binary tree in the binary beanstalk

EXAMPLE

8 is present, because 12, 13 and 14 are the three leaves (terms of A055938) nearest to 8, and A011371(12) = A011371(13) = 10, A011371(14) = 11, A011371(10) = A011371(11) = 8 (thus it takes two iterations of A011371 to reach 8 from any of those three leaves). See also Paul Tek's illustration.

PROG

(Scheme, with Antti Karttunen's IntSeq-library)

(define A257509 (MATCHING-POS 1 0 (lambda (n) (= 2 (A257265 n)))))

(Haskell)

a257509 n = a257509_list !! (n-1)

a257509_list = filter ((== 2) . a257265) [0..]

-- Reinhard Zumkeller, May 06 2015

CROSSREFS

First differences: A256489.

Positions of 2's in A257265.

Subsequence of A005187.

Cf. A011371, A055938, A257508, A257264.

Sequence in context: A092456 A232724 A260409 * A232570 A029522 A033309

Adjacent sequences:  A257506 A257507 A257508 * A257510 A257511 A257512

KEYWORD

nonn

AUTHOR

Antti Karttunen, May 03 2015

STATUS

approved

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Last modified January 20 14:40 EST 2019. Contains 319333 sequences. (Running on oeis4.)