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A181497
a(n) is the smallest m such that A056753(m) = 2*n + 1.
3
0, 1, 3, 7, 11, 19, 27, 35, 43, 59, 75, 91, 107, 123, 139, 155, 171, 203, 235, 267, 299, 331, 363, 395, 427, 459, 491, 523, 555, 587, 619, 651, 683, 747, 811, 875, 939, 1003, 1067, 1131, 1195, 1259, 1323, 1387, 1451, 1515, 1579, 1643, 1707, 1771, 1835, 1899
OFFSET
0,3
COMMENTS
A056753(a(n)) = A005408(n) and A056753(m) < A005408(n) for m < a(n).
LINKS
MAPLE
a:= proc(n) option remember; `if`(n<2, n,
(h-> 2*a(n-h)-1+2*a(h))(iquo(n, 2)))
end:
seq(a(n), n=0..60); # Alois P. Heinz, Jul 26 2019
MATHEMATICA
a[n_] := a[n] = If[n < 2, n, 2 a[n-#] - 1 + 2 a[#]&[Quotient[n, 2]]];
a /@ Range[0, 60] (* Jean-François Alcover, Nov 04 2020, after Alois P. Heinz *)
PROG
(Magma) T:=[]; S:=[ 0: n in [1..2000] ]; k:=1; p:=Position(S, 0, 1); while p gt 0 do for j in [p..#S by k+1] do if S[j] eq 0 then S[j]:=k; else break; end if; end for; f:=p; Append(~T, p-1); p:=Position(S, 0, f); k+:=2; end while; T; // Klaus Brockhaus, Oct 25 2010
CROSSREFS
Sequence in context: A329482 A049754 A191114 * A292095 A265323 A346912
KEYWORD
nonn,look
AUTHOR
Reinhard Zumkeller, Oct 24 2010
STATUS
approved