A192776 Squares of binary palindromes.

0, 1, 1001, 11001, 110001, 1010001, 11100001, 100100001, 110111001, 1011011001, 1111000001, 10001000001, 11111101001, 101000101001, 111110000001, 1000010000001, 1010011010001, 1110000111001, 10000111001001, 10011001001001, 10110010111001, 11011101010001, 11111100000001, 100000100000001, 101101101110001, 110101001011001, 1000101110001001, 1001010010001001, 1011101101011001, 1101000001110001, 1111111000000001, 10000001000000001, 10010001100100001

Offset

1,3

Links

Table of n, a(n) for n=1..33.

Prog

(Python)
def A192776(n):
    if n == 1: return 0
    a = 1<<(l:=n.bit_length()-2)
    m = a|(n&a-1)
    return int(bin(((m<<l+1)+int(bin(m)[-1:1:-1]or'0', 2) if a&n else (m<<l)+int(bin(m)[-2:1:-1]or'0', 2))**2)[2:]) # Chai Wah Wu, Jul 23 2024

Crossrefs

This is A192775 written in base 2, also A006995 (or A057148) squared. Cf. A006995, A057148.

Sequence in context: A114387 A357774 A204965 * A218640 A221347 A109431

Adjacent sequences: A192773 A192774 A192775 * A192777 A192778 A192779

Keyword

nonn,base

Author

N. J. A. Sloane, Jul 09 2011

Status

approved