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A291962
Decimal repunits written in base 2.
9
0, 1, 1011, 1101111, 10001010111, 10101101100111, 11011001000000111, 100001111010001000111, 101010011000101011000111, 110100111110110101111000111, 1000010001110100011010111000111, 1010010110010001100001100111000111, 1100111011110101111010000000111000111
OFFSET
0,3
COMMENTS
Interpreting A002275 as binary numbers and converting to decimal gives A000225. This sequence gives the resulting terms of the "reverse" operation.
The n least significant bits of a(n) seem to converge to A088911 as n increases.
LINKS
FORMULA
a(n) = A007088(A002275(n)).
MATHEMATICA
Table[FromDigits@ IntegerDigits[Floor[10^n/9], 2], {n, 0, 12}] (* Michael De Vlieger, Sep 06 2017 *)
FromDigits[IntegerDigits[#, 2]]&/@Table[FromDigits[PadRight[{}, n, 1]], {n, 0, 20}] (* Harvey P. Dale, Apr 01 2023 *)
PROG
(PARI) a(n) = subst(Pol(binary((10^n-1)/9)), x, 10)
(Python)
def a(n): return 0 if n == 0 else int(bin(int("1"*n))[2:])
print([a(n) for n in range(13)]) # Michael S. Branicky, Apr 26 2022
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Felix Fröhlich, Sep 06 2017
STATUS
approved