A081431 -id:A081431 - cp's OEIS frontend

A081432 RevDecimal(RevBinary(n)), where RevDecimal(m) is the decimal reversal of m (A004086) and RevBinary(m) is the binary reversal of m (A030101).

0, 1, 1, 3, 1, 5, 3, 7, 1, 9, 5, 31, 3, 11, 7, 51, 1, 71, 9, 52, 5, 12, 31, 92, 3, 91, 11, 72, 7, 32, 51, 13, 1, 33, 71, 94, 9, 14, 52, 75, 5, 73, 12, 35, 31, 54, 92, 16, 3, 53, 91, 15, 11, 34, 72, 95, 7, 93, 32, 55, 51, 74, 13, 36, 1, 56, 33, 79, 71, 18, 94, 311, 9, 37, 14

Offset: 0

Reinhard Zumkeller, Mar 20 2003

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Cf. A030101, A004086.

Cf. A081431, A081433, A007088.

IntegerReverse[IntegerReverse[Range[0,80],2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Oct 03 2017 *)

a(n) = fromdigits(Vecrev(digits(fromdigits(Vecrev(binary(n)), 2)))); \\ Michel Marcus, Jan 30 2023

def a(n): return int(str(int(bin(n)[:1:-1], 2))[::-1])
print([a(n) for n in range(75)]) # Michael S. Branicky, Jan 30 2023

a(n) = A004086(A030101(n)). - Michel Marcus, Jan 30 2023

A081433 Numbers n such that RevBinary(RevDecimal(n))=RevDecimal(RevBinary(n)), where RevDecimal(n) is the decimal reversal of n (A004086) and RevBinary(n) is the binary reversal of n (A030101).

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 15, 33, 51, 66, 99, 165, 313, 516, 535, 561, 585, 615, 626, 717, 759, 858, 929, 957, 1241, 1421, 2112, 2482, 2552, 2842, 3579, 4224, 5485, 5845, 6336, 7447, 8448, 9009, 9753, 11051, 12631, 13621, 15011, 15351, 15375

Offset: 1

Reinhard Zumkeller, Mar 20 2003

A030101(A004086(a(n)))=A004086(A030101(a(n))), A081431(a(n))=A081432(a(n)).

Cf. A081432, A081434, A007088.

def ok(n): return int(bin(int(str(n)[::-1]))[:1:-1], 2) == int(str(int(bin(n)[:1:-1], 2))[::-1])
print([k for k in range(2**14) if ok(k)]) # Michael S. Branicky, Jan 30 2023

cp's OEIS Frontend

A081432 RevDecimal(RevBinary(n)), where RevDecimal(m) is the decimal reversal of m (A004086) and RevBinary(m) is the binary reversal of m (A030101).

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