|
%I #9 Mar 30 2012 18:50:49
%S 0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,3,3,3,4,
%T 4,4,4,4,4,4,5,6,6,6,7,7,7,7,7,7,8,9,10,10,10,11,11,11,11,11,12,13,14,
%U 15,15,15,16,16,16,16,17,18,19,20,21,21,21,22,22,22,23,24,25,26,27,28,28
%N Number of Hannah Rollman's numbers <= n.
%C a(n) = #{k: A048992(k)<=n} = n - #{k: A048991(k)<=n};
%C a(n) < n/2 for n < 740; a(n) > n/2 for 740 < n < 1260,
%C see A105391 for numbers m with a(m) = m/2.
%H Klaus Brockhaus, <a href="/A105390/b105390.txt">Table of n, a(n) for n = 1..6000</a>
%H Klaus Brockhaus, <a href="/A105390/a105390.gif">Plots of A105390(n)/n at various scales</a>
%o (JBASIC, from _Klaus Brockhaus_, Aug 15 2007)
%o s$ = "" : d = 0
%o FOR n = 1 TO 100
%o sn$ = str$(n)
%o IF instr(s$, sn$) > 0 THEN d = d+1 ELSE s$ = s$ + sn$
%o print d ; ",";
%o NEXT
%Y Cf. A048991, A048992, A105391, A131981.
%K nonn,base
%O 1,23
%A _Reinhard Zumkeller_, Apr 04 2005
|
