A281313 Write n in Elias's delta code, interchange the 1's and 0's and convert it back to decimal.

0, 7, 6, 11, 10, 9, 8, 63, 62, 61, 60, 59, 58, 57, 56, 111, 110, 109, 108, 107, 106, 105, 104, 103, 102, 101, 100, 99, 98, 97, 96, 191, 190, 189, 188, 187, 186, 185, 184, 183, 182, 181, 180, 179, 178, 177, 176, 175, 174, 173, 172, 171, 170, 169, 168, 167, 166, 165, 164, 163, 162

Offset: 1

Author

Indranil Ghosh, Jan 19 2017

Keywords

• nonn
• base

Examples

			For n = 10, the Elias delta code for 10 is '11000010' and after interchanging the 0's and 1's it becomes '00111101'. Now, 111101_2 = 61_10. So, a(10) = 61.
		

Links

• Indranil Ghosh, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A035327, A054429 (n is converted to Elias gamma code, the 1's and 0's are interchanged and the code is converted back to decimal, for n>1), A281150.

Programs

Python

def a(n):
    s=""
    for i in A281150(n):
        if i=="1":
            s+="0"
        else:
            s+="1"
    return int(s, 2)