The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A316758 A self-"read and extend" sequence built following the rules visible in the Comments section. 3
 1, 2, 4, 8, 16, 32, 46, 92, 841, 1268, 2356, 1247, 9442, 14888, 97762, 955421, 554219, 113488, 226679, 334558, 966611, 1222339, 2444678, 3456889, 9877631, 12255679, 11234558, 11224669, 22334489, 98876644, 88766449, 988775321, 9776554210, 112345589, 112246789, 122467891, 224678911, 223445789 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Start with a(1) = 1 and a(2) = 2; read the sequence digit by digit starting from the left: when the read digit is smaller than the next one, double the last integer of the sequence and extend the sequence with the result rearranged (smallest digits first and leading zeros erased); when the read digit is bigger than the next one, double the last integer of the sequence and extend the sequence with the result rearranged (biggest digits first, zeros at the end); when both digits are equal, do a circular permutation of the last integer of the sequence and extend the sequence with the result (this will erase a few zeros in some cases, as 100023850 becomes 238501). LINKS Jean-Marc Falcoz, Table of n, a(n) for n = 1..3002 EXAMPLE As the only digit of a(1) = 1 is smaller than 2 (the next digit), we extend the sequence with 4 (that is 2 times 2); as the only digit of a(2) = 2 is smaller than 4 (the next digit), we extend the sequence with 8 (that is 2 times 4); as the only digit of a(3) = 4 is smaller than 8 (the next digit), we extend the sequence with 16 (that is 2 times 8 -- with 1 coming before 6); as the only digit of a(4) = 8 is bigger than 1 (the next digit), we extend the sequence with 32 (that is 2 times 16 -- with 3 coming before 2); as the first digit of a(5) = 1 is smaller than 6 (the next digit), we extend the sequence with 46 (that is 2 times 32 = 64 that is rearranged in 46); as the last digit of a(5) = 6 is bigger than 3 (the next digit), we extend the sequence with 92 (that is 2 times 46 = 92 rearranged in 29); . . . as the last digit of a(9) = 1 is equal to 1 (the next digit), we extend the sequence with 554219 (this is the circular permutation of the previous term, 955421); etc. CROSSREFS Cf. A316749 and A316750 (for other sets of "read and extend" rules). Sequence in context: A335019 A337719 A289275 * A316750 A008382 A208742 Adjacent sequences: A316755 A316756 A316757 * A316759 A316760 A316761 KEYWORD nonn,base AUTHOR Jean-Marc Falcoz and Eric Angelini, Jul 12 2018 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 5 18:09 EDT 2023. Contains 363138 sequences. (Running on oeis4.)