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A085765
Partial sums and bisection of A086450.
3
1, 2, 4, 5, 9, 11, 16, 17, 26, 30, 41, 43, 59, 64, 81, 82, 108, 117, 147, 151, 192, 203, 246, 248, 307, 323, 387, 392, 473, 490, 572, 573, 681, 707, 824, 833, 980, 1010, 1161, 1165, 1357, 1398, 1601, 1612, 1858, 1901, 2149, 2151, 2458, 2517
OFFSET
0,2
COMMENTS
Sum of inverses of a(n) is 1.5398789314089581123...
Conjecture: log(a(n))/log(n) grows unboundedly.
Conjecture: a(n) mod 2 repeats the 7-pattern 0,0,1,1,1,0,1.
The conjecture concerning the mod 2 pattern follows directly from the corresponding conjecture proved in A086450. - Lambert Herrgesell (zero815(AT)googlemail.com), May 08 2007
LINKS
FORMULA
a(n) = A086450(2n) = A086450(0) + ... + A086450(n). - Charles R Greathouse IV, Sep 26 2013
MAPLE
b:= proc(n) local m; b(n):= `if`(n=0, 1,
`if`(irem(n, 2, 'm')=1, b(m), a(m)))
end:
a:= proc(n) a(n):= b(n) +`if`(n=0, 0, a(n-1)) end:
seq(a(n), n=0..100); # Alois P. Heinz, Sep 26 2013
MATHEMATICA
b[0] = 1;
b[n_] := b[n] = If[EvenQ[n], Sum[b[n/2-k], {k, 0, n/2}], b[(n-1)/2]]; A085765 = Table[b[n], {n, 0, 100}] // Accumulate (* Jean-François Alcover, Mar 28 2017 *)
PROG
(PARI) v=vector(1000); v[1]=1; s=1; for(n=2, 1000, v[n]=if(n%2==0, v[n/2], s=s+v[(n+1)/2]; print1(s", "); s))
(PARI) lista(nn) = {v=vector(nn); v[1]=1; s=1; for(n = 2, nn, v[n]= if(n%2==0, v[n/2], s=s+v[(n+1)/2])); forstep(i = 1, nn, 2, print1(v[i], ", "); ); } \\ Michel Marcus, Sep 26 2013
CROSSREFS
Sequence in context: A258652 A065514 A152186 * A211521 A039871 A365042
KEYWORD
nonn,easy
AUTHOR
Ralf Stephan, Jul 22 2003
STATUS
approved