# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a325095 Showing 1-1 of 1 %I A325095 #17 Jul 27 2019 14:57:51 %S A325095 1,2,4,5,10,12,14,15,30,35,40,42,47,49,51,52,104,119,134,139,154,159, %T A325095 164,166,181,186,191,193,198,200,202,203,406,458,510,525,577,592,607, %U A325095 612,664,679,694,699,714,719,724,726,778,793,808,813,828,833,838,840 %N A325095 Number of subsets of {1...n} with no binary carries. %C A325095 A binary carry of two positive integers is an overlap of the positions of 1's in their reversed binary expansion. For example, the binary representations of {2,5,8} are: %C A325095 2 = 10, %C A325095 5 = 101, %C A325095 8 = 1000, %C A325095 and since there are no columns with more than one 1, {2,5,8} is counted under a(8). %H A325095 Alois P. Heinz, Table of n, a(n) for n = 0..16383 %F A325095 a(2^n - 1) = A000110(n + 1). %e A325095 The a(1) = 1 through a(7) = 15 subsets: %e A325095 {} {} {} {} {} {} {} %e A325095 {1} {1} {1} {1} {1} {1} {1} %e A325095 {2} {2} {2} {2} {2} {2} %e A325095 {1,2} {3} {3} {3} {3} {3} %e A325095 {1,2} {4} {4} {4} {4} %e A325095 {1,2} {5} {5} {5} %e A325095 {1,4} {1,2} {6} {6} %e A325095 {2,4} {1,4} {1,2} {7} %e A325095 {3,4} {2,4} {1,4} {1,2} %e A325095 {1,2,4} {2,5} {1,6} {1,4} %e A325095 {3,4} {2,4} {1,6} %e A325095 {1,2,4} {2,5} {2,4} %e A325095 {3,4} {2,5} %e A325095 {1,2,4} {3,4} %e A325095 {1,2,4} %p A325095 b:= proc(n, t) option remember; `if`(n=0, 1, b(n-1, t)+ %p A325095 `if`(Bits[And](n, t)=0, b(n-1, Bits[Or](n, t)), 0)) %p A325095 end: %p A325095 a:= n-> b(n, 0): %p A325095 seq(a(n), n=0..63); # _Alois P. Heinz_, Mar 28 2019 %t A325095 binpos[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1]; %t A325095 stableQ[u_,Q_]:=!Apply[Or,Outer[#1=!=#2&&Q[#1,#2]&,u,u,1],{0,1}]; %t A325095 Table[Length[Select[Subsets[Range[n]],stableQ[#,Intersection[binpos[#1],binpos[#2]]!={}&]&]],{n,0,10}] %Y A325095 Cf. A000110, A019565, A050315, A080572, A247935, A267610, A267700. %Y A325095 Cf. A325094, A325096, A325097, A325100, A325103, A325104, A325105. %K A325095 nonn,look %O A325095 0,2 %A A325095 _Gus Wiseman_, Mar 27 2019 %E A325095 a(16)-a(55) from _Alois P. Heinz_, Mar 28 2019 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE