A211676 Number of n-bit numbers in A077436.

1, 1, 2, 3, 4, 5, 6, 9, 14, 24, 37, 63, 93, 162, 233, 376, 582, 921, 1497, 2435, 4007, 6696, 10998, 18310, 30340, 50792, 84897, 143079, 239266, 401652, 673887, 1131226, 1900203, 3197114, 5373366, 9039360, 15208992, 25592325, 43064747, 72494816, 122025100

Offset: 0

Author

T. D. Noe, Apr 27 2012

Keywords

• nonn
• hard
• base

Comments

That is, the number of binary numbers b having n bits and B(b) = B(b^2), where the function B gives the number of ones in a binary number. For numbers written in base 10, the corresponding sequence is A147523.

Crossrefs

Cf. A077436, A147523.

Programs

Mathematica

Join[{1}, Table[cnt = 0; Do[If[Total[IntegerDigits[i, 2]] == Total[IntegerDigits[i^2, 2]], cnt++], {i, 2^(n-1), 2^n-1}]; cnt, {n, 15}]]

Extensions

a(28)-a(38) from Donovan Johnson, Apr 29 2012

a(39)-a(40) from Donovan Johnson, Aug 25 2012