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A298476 Least k such that A298475(k) = n. 2
1, 2, 37, 203, 1332, 13428, 160884, 858740, 10295924, 54958708, 658938484, 3517356660 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
A298474(n) = floor(log_2(a(n))) + 1.
LINKS
Rémy Sigrist, C program for A298476
FORMULA
a(n) >= 2^(A298474(n) - 1).
a(n) < 2^A298474(n).
EXAMPLE
The smallest partition of the binary representation of A298476(k) is:
k | A298476(k) | partition
--+------------+---------------------------------------
1 | 1 | (1)_2
2 | 2 | (1)(0)_2
3 | 37 | (1001)(0)(1)_2
4 | 203 | (11)(00)(101)(1)_2
5 | 1332 | (101)(00)(1)(101)(00)_2
6 | 13428 | (11)(010)(0)(01110)(1)(00)_2
7 | 160884 | (1001)(1)(101)(000)(111)(010)(0)_2
8 | 858740 | (11)(010)(0)(0110)(1001)(11)(010)(0)_2
MATHEMATICA
With[{s = {1, 2}~Join~Array[Function[w, Min@ Map[Length, Select[#, And[AllTrue[#, PalindromeQ], Union@ Map[Length, #] != {1}] &]] &@ Union@ Map[Select[SplitBy[#, IntegerQ], IntegerQ@ First@ # &] &, Map[Insert[w, ".", #] &, Map[{#} &, Rest@ Subsets@ Range@ Length@ w, {2}]]]]@ IntegerDigits[#, 2] &, 1400, 3]}, Array[FirstPosition[s, #][[1]] &, Max@ Take[#, 1 + LengthWhile[Differences@ #, # == 1 &]] &@ Union@ s]] (* Michael De Vlieger, Jan 23 2018 *)
PROG
(C) See Links section.
CROSSREFS
Sequence in context: A134596 A139119 A244757 * A302883 A053788 A078976
KEYWORD
nonn,base,more
AUTHOR
Peter Kagey, Jan 19 2018
EXTENSIONS
a(9)-a(12) from Rémy Sigrist, Dec 28 2019
STATUS
approved

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Last modified March 19 03:33 EDT 2024. Contains 370952 sequences. (Running on oeis4.)