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 A105391 Numbers m such that there are an equal number of numbers <= m that are contained and that are not contained in the concatenation of terms <= m in A048991. 3
 740, 1260, 1262, 5230, 15804, 15814, 15816, 36294, 194876, 213868 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A105390(a(n)) = a(n)/2. There are no other terms <= 600000. The plots in a105390.gif strongly suggest that the sequence is complete. - Klaus Brockhaus, Aug 15 2007 LINKS Nick Hobson, Python program for this sequence EXAMPLE A105390(n) < n/2 for n < a(1)=740; A105390(n) > n/2 for n with 740 < n < a(2)=1260; A105390(1261)=631, A105390(a(3))=A105390(1262)=631; A105390(n) < n/2 for n with 1262 < n < a(4)=5230; A105390(n) > n/2 for n with 5230 < n < a(5)=15804; A105390(n) < n/2 for n with 15804 < n < a(6)=15814; A105390(15815)=7908, A105390(a(7))=A105390(15816)=7909; A105390(n) < n/2 for n with 15816 < n < a(8)=36294; A105390(n) > n/2 for n with 36294 < n < a(9)=194876; etc. PROG (JBASIC) s\$ = "" : c = 0 : d = 0 FOR n = 1 TO 40000 sn\$ = str\$(n) IF instr(s\$, sn\$) > 0 THEN d = d+1 ELSE c = c+1 : s\$ = s\$ + sn\$ IF c = d THEN print n ; ", " ; NEXT ' Klaus Brockhaus, Aug 15 2007 CROSSREFS Cf. A048991, A048992, A105390, A131982 (numbers n such that A131981(n) = n/2). Sequence in context: A066402 A243778 A256634 * A319043 A044984 A252576 Adjacent sequences:  A105388 A105389 A105390 * A105392 A105393 A105394 KEYWORD nonn,base,more AUTHOR Reinhard Zumkeller, Apr 04 2005 STATUS approved

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Last modified August 16 07:50 EDT 2022. Contains 356160 sequences. (Running on oeis4.)