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A218790 a(n) = binary code (shown here in decimal) of the position of the predecessor of the natural number pair (2n,2n+1) in the compact beanstalk-tree A218782. 4
1, 3, 5, 13, 21, 37, 53, 117, 181, 309, 437, 693, 949, 1717, 1461, 3509, 5557, 9653, 13749, 21941, 30133, 54709, 46517, 79285, 112053, 210357, 177589, 472501, 308661, 734645, 996789, 2045365, 3093941, 5191093, 7288245, 11482549, 15676853, 28259765, 24065461 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..1024

FORMULA

a(n) = A218614(A005187(n)).

PROG

(Scheme with memoization-macro definec): (definec (A218790 n) (cond ((< n 2) n) ((A011371 (* 2 n)) => (lambda (bp) (if (even? bp) (A004754 (A218790 (/ bp 2))) (A004755 (A218790 (/ (-1+ bp) 2))))))))

CROSSREFS

Subset of A218614, i.e. a(n) = A218614(A005187(n)).

Also, a(n) = A054429(A218791(n)). Used to construct A218782, A218783. Cf. also A218787, A218788

Sequence in context: A290441 A222752 A172143 * A168388 A059872 A059873

Adjacent sequences:  A218787 A218788 A218789 * A218791 A218792 A218793

KEYWORD

nonn,base

AUTHOR

Antti Karttunen, Nov 16 2012

STATUS

approved

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Last modified January 21 17:45 EST 2019. Contains 319349 sequences. (Running on oeis4.)