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A341709
Write n as a sum of powers of 2 then replace each power of 2 in the sum by its decimal reversal A004094(n).
3
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 46, 47, 48, 49, 50, 51, 52, 53, 54
OFFSET
0,3
COMMENTS
Suggest by Eric Angelini's yranib sequence A341707.
LINKS
N. J. A. Sloane, Exciting Number Sequences (video of talk), Mar 05 2021.
EXAMPLE
17 = 16+1 becomes 1+61 = 62 = a(17).
MAPLE
revbin:= n-> (s-> parse(cat(s[-i]$i=1..length(s))))(""||(2^n)): # A004094
f:=proc(n) local t1, i;
t1:=convert(n, base, 2);
add(t1[i]*revbin(i-1), i=1..nops(t1));
end:
seq(f(n), n=0..72);
PROG
(Python)
def A341709(n):
m, c = 1, 0
while n > 0:
n, b = divmod(n, 2)
c += b*int(str(m)[::-1])
m *= 2
return c # Chai Wah Wu, Feb 18 2021
CROSSREFS
Sequence in context: A248502 A250039 A132032 * A055645 A262545 A043320
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Feb 18 2021
STATUS
approved