cp's OEIS Frontend

A342036 Palindromes of even length only using 0 or 1.

%I A342036 #45 Dec 27 2022 08:59:10
%S A342036 0,11,1001,1111,100001,101101,110011,111111,10000001,10011001,
%T A342036 10100101,10111101,11000011,11011011,11100111,11111111,1000000001,
%U A342036 1000110001,1001001001,1001111001,1010000101,1010110101,1011001101,1011111101,1100000011,1100110011
%N A342036 Palindromes of even length only using 0 or 1.
%C A342036 Subsequence of A057148.
%C A342036 a(n) is a multiple of 11.
%F A342036 a(n) = A007088(n) * 10^A070939(n) + A305989(n).
%F A342036 a(n) = A007088(A048701(n)). - _Michel Marcus_, Feb 26 2021
%e A342036 A006995|A057148|A048701|A342036|A048700|A342040
%e A342036 -------+-------+-------+-------+-------+-------
%e A342036      0 |     0 |     0 |     0 |       |
%e A342036      1 |     1 |       |       |     1 |     1
%e A342036      3 |    11 |     3 |    11 |       |
%e A342036      5 |   101 |       |       |     5 |   101
%e A342036      7 |   111 |       |       |     7 |   111
%e A342036      9 |  1001 |     9 |  1001 |       |
%e A342036     15 |  1111 |    15 |  1111 |       |
%e A342036     17 | 10001 |       |       |    17 | 10001
%t A342036 Array[FromDigits@ Join[#, Reverse[#]] &@ IntegerDigits[#, 2] &, 26, 0] (* _Michael De Vlieger_, Feb 26 2021 *)
%o A342036 (Ruby)
%o A342036 def A(n)
%o A342036   str = n.to_s(2)
%o A342036   (str + str.reverse).to_i
%o A342036 end
%o A342036 def A342036(n)
%o A342036   (0..n).map{|i| A(i)}
%o A342036 end
%o A342036 p A342036(30)
%o A342036 (Python)
%o A342036 def a(n): b = bin(n)[2:]; return int(b+b[::-1])
%o A342036 print([a(n) for n in range(27)]) # _Michael S. Branicky_, Feb 26 2021
%Y A342036 Cf. A006995, A007088, A048701, A057148, A070939, A305989, A342040.
%K A342036 nonn,easy,base
%O A342036 0,2
%A A342036 _Seiichi Manyama_, Feb 26 2021
%E A342036 Offset changed to 0 by _Andrey Zabolotskiy_, Dec 26 2022