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A080719 Replace decimal digits with their binary values and convert back to decimal representation. 4
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 2, 3, 6, 7, 12, 13, 14, 15, 24, 25, 4, 5, 10, 11, 20, 21, 22, 23, 40, 41, 6, 7, 14, 15, 28, 29, 30, 31, 56, 57, 8, 9, 18, 19, 36, 37, 38, 39, 72, 73, 10, 11, 22, 23, 44, 45, 46, 47, 88, 89, 12, 13, 26, 27, 52, 53, 54, 55, 104, 105, 14, 15, 30, 31, 60, 61, 62 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
m is a local maximum iff m == 9 modulo 10 (see A017377).
A257831 seen as binary numbers: A007088(a(n)) = A257831(n). - Reinhard Zumkeller, May 10 2015
LINKS
EXAMPLE
n=27 -> '2''7' -> '10''111' -> '10111' -> 23: a(27)=23.
See also A257831.
MATHEMATICA
Table[FromDigits[Flatten[IntegerDigits[#, 2]&/@IntegerDigits[n]], 2], {n, 80}] (* Harvey P. Dale, Aug 30 2014 *)
PROG
(Haskell)
import Data.Maybe (mapMaybe)
a080719 = foldr (\b v -> 2 * v + b) 0 .
concat . mapMaybe (flip lookup bin) . a031298_row
where bin = zip [0..9] a030308_tabf
-- Reinhard Zumkeller, May 10 2015
(Python)
def A080719(n):
....return int(''.join((format(int(d), 'b') for d in str(n))), 2)
# Chai Wah Wu, May 10 2015
CROSSREFS
Cf. A007088.
Sequence in context: A038506 A091047 A068505 * A049105 A125959 A043269
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Mar 06 2003
EXTENSIONS
a(0)=0 prepended and offset changed by Reinhard Zumkeller, May 10 2015
STATUS
approved

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Last modified June 20 18:00 EDT 2024. Contains 373532 sequences. (Running on oeis4.)