OFFSET
1,5
COMMENTS
Number of i such that |d(i) - d(i-1)| = 1, where Sum_{i=0..m} d(i)*2^i is the base-2 representation of n.
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
Paul Barry, Conjectures and results on some generalized Rueppel sequences, arXiv:2107.00442 [math.CO], 2021.
MAPLE
A037834 := proc(n)
local dgs ;
dgs := convert(n, base, 2);
add( abs(op(i, dgs)-op(i-1, dgs)), i=2..nops(dgs)) ;
end proc: # R. J. Mathar, Oct 16 2015
MATHEMATICA
Table[Total@ Flatten@ Map[Abs@ Differences@ # &, Partition[ IntegerDigits[n, 2], 2, 1]], {n, 90}] (* Michael De Vlieger, May 09 2017 *)
PROG
(Haskell)
a037834 n = sum $ map fromEnum $ zipWith (/=) (tail bs) bs
where bs = a030308_row n
-- Reinhard Zumkeller, Feb 20 2014
(Python)
def A037834(n): return (n^(n>>1)).bit_count()-1 # Chai Wah Wu, Jul 13 2024
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved