

A211676


Number of nbit numbers in A077436.


1



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
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OFFSET

0,3


COMMENTS

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


LINKS

Table of n, a(n) for n=0..40.


MATHEMATICA

Join[{1}, Table[cnt = 0; Do[If[Total[IntegerDigits[i, 2]] == Total[IntegerDigits[i^2, 2]], cnt++], {i, 2^(n1), 2^n1}]; cnt, {n, 15}]]


CROSSREFS

Cf. A077436, A147523.
Sequence in context: A228669 A200444 A211697 * A076299 A136683 A200332
Adjacent sequences: A211673 A211674 A211675 * A211677 A211678 A211679


KEYWORD

nonn,hard,base


AUTHOR

T. D. Noe, Apr 27 2012


EXTENSIONS

a(28)a(38) from Donovan Johnson, Apr 29 2012
a(39)a(40) from Donovan Johnson, Aug 25 2012


STATUS

approved



