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A276624
The infinite trunk of ternary beanstalk with reversed subsections.
3
0, 2, 8, 4, 26, 20, 16, 12, 10, 80, 72, 68, 62, 56, 52, 46, 42, 38, 34, 30, 28, 242, 232, 224, 216, 212, 204, 198, 194, 188, 180, 176, 170, 164, 160, 152, 144, 140, 134, 126, 122, 116, 110, 106, 100, 96, 92, 88, 84, 82, 728, 716, 706, 698, 688, 680, 672, 664, 656, 648, 644, 634, 626, 618, 610, 602, 594, 590, 582, 576, 572
OFFSET
0,2
COMMENTS
See A276623.
LINKS
FORMULA
a(0) = 0; a(1) = 2; for n > 1, if 2*A054861(a(n-1))+1 is not a power of 3, then a(n) = 2*A054861(a(n-1)), otherwise a(n) = A000244(1+A081604(1+2*A054861(a(n-1)))) - 1.
PROG
(Scheme)
(definec (A276624 n) (cond ((zero? n) n) ((= n 1) 2) (else (let ((maybe_next (* 2 (A054861 (A276624 (- n 1)))))) (if (not (= 1 (A053735 (+ 1 maybe_next)))) maybe_next (+ -1 (A000244 (+ 1 (A081604 (+ 1 maybe_next))))))))))
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Sep 11 2016
STATUS
approved