A233268 The middle point of row n in binary beanstalk related sequences A179016, A218602, A218616, A233270, A233271.

1, 2, 3, 6, 10, 17, 30, 53, 95, 171, 310, 564, 1036, 1918, 3574, 6691, 12566, 23653, 44610, 84309, 159698, 303253, 577352, 1102121, 2109448, 4047967, 7787277, 15015347, 29011671, 56150867, 108825599, 211127246, 409886210, 796134319, 1546848744, 3006198333, 5843799964

Offset

1,2

Comments

a(n) points to the center of each palindromic row/subrange of A233270, and to the lower position nearest to the center, if the length of range is even.

For all n, A218602(a(n)) = a(n) + (1-A000035(A213709(n-1))).

Links

Table of n, a(n) for n=1..37.

Formula

a(n) = floor((A213710(n-1) + A218600(n)) / 2).

a(n) = A218600(n-1) + ceiling((A213709(n-1)/2)).

Prog

(MIT/GNU Scheme, two alternative versions)
(define (A233268 n) (floor->exact (/ (+ (A213710 (- n 1)) (A218600 n)) 2)))
(define (A233268 n) (+ (A218600 (- n 1)) (ceiling->exact (/ (A213709 (- n 1)) 2))))

Crossrefs

Cf. A213709, A213710, A218600, A234018, A234019, A234020.

Cf. also A179016, A218602, A218616, A233270, A233271.

Sequence in context: A285665 A135431 A123908 * A026397 A193200 A026779

Adjacent sequences: A233265 A233266 A233267 * A233269 A233270 A233271

Keyword

nonn

Author

Antti Karttunen, Dec 29 2013

Status

approved