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 A144079 a(n) = the number of digits in the binary representation of n that equal the corresponding digit in the binary reversal of n. (I.e., a(n) = number of 0's in n XOR A030101(n).) 2
 1, 0, 2, 1, 3, 1, 3, 2, 4, 0, 2, 0, 2, 2, 4, 3, 5, 1, 3, 3, 5, 1, 3, 1, 3, 3, 5, 1, 3, 3, 5, 4, 6, 2, 4, 2, 4, 0, 2, 2, 4, 0, 2, 4, 6, 2, 4, 2, 4, 4, 6, 0, 2, 2, 4, 0, 2, 2, 4, 2, 4, 4, 6, 5, 7, 3, 5, 3, 5, 1, 3, 5, 7, 3, 5, 3, 5, 1, 3, 3, 5, 1, 3, 5, 7, 3, 5, 3, 5, 1, 3, 5, 7, 3, 5, 3, 5, 5, 7, 1, 3, 3, 5, 3, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS A144078(n) + a(n) = A070939(n), the number of binary digits in n. LINKS EXAMPLE 20 in binary is 10100. Compare this with its digit reversal, 00101. XOR each pair of corresponding digits: 1 XOR 0 = 1, 0 XOR 0 = 0, 1 XOR 1 = 0, 0 XOR 0 = 0, 0 XOR 1 = 1. There are three bit pairs that contain the same values, so a(20) = 3. MAPLE A144079 := proc(n) local a, dgs, i; a := 0 ; dgs := convert(n, base, 2) ; for i from 1 to nops(dgs) do if op(i, dgs)+op(-i, dgs) <> 1 then a := a+1 ; fi; od; RETURN(a) ; end: for n from 1 to 240 do printf("%d, ", A144079(n)) ; od: # R. J. Mathar, Sep 14 2008 MATHEMATICA Table[With[{c=IntegerDigits[n, 2]}, Count[BitXor[c, Reverse[c]], 0]], {n, 110}] (* Harvey P. Dale, Sep 03 2015 *) CROSSREFS Cf. A030101, A144078. Sequence in context: A109698 A029231 A025808 * A326839 A071575 A307908 Adjacent sequences:  A144076 A144077 A144078 * A144080 A144081 A144082 KEYWORD base,nonn AUTHOR Leroy Quet, Sep 09 2008 EXTENSIONS More terms from R. J. Mathar, Sep 14 2008 STATUS approved

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Last modified June 7 02:48 EDT 2020. Contains 334836 sequences. (Running on oeis4.)