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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A144789 Consider the runs of 0's in the binary representation of n, each of these runs being on the edge of the binary representation n and/or being bounded by 1's. a(n) = the length of the shortest such run (with positive length) of 0's in binary n. a(n) = 0 if there are no runs of 0's in binary n.

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%I A144789 #16 Apr 06 2020 19:35:23
%S A144789 0,1,0,2,1,1,0,3,2,1,1,2,1,1,0,4,3,1,2,1,1,1,1,3,2,1,1,2,1,1,0,5,4,1,
%T A144789 3,2,1,1,2,1,1,1,1,1,1,1,1,4,3,1,2,1,1,1,1,3,2,1,1,2,1,1,0,6,5,1,4,2,
%U A144789 1,1,3,2,2,1,1,2,1,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,5,4,1,3,2,1,1,2,1,1
%N A144789 Consider the runs of 0's in the binary representation of n, each of these runs being on the edge of the binary representation n and/or being bounded by 1's. a(n) = the length of the shortest such run (with positive length) of 0's in binary n. a(n) = 0 if there are no runs of 0's in binary n.
%e A144789 20 in binary is 10100. The runs of 0's are as follows: 1(0)1(00). The shortest of these runs contains exactly one 0's So a(20) = 1.
%p A144789 A007814 := proc(n) local nshf,a ; a := 0 ; nshf := n ; while nshf mod 2 = 0 do nshf := nshf/2 ; a := a+1 ; od: a ; end: A144789 := proc(n) option remember ; local lp2,lp2sh,bind ; bind := convert(n,base,2) ; if add(i,i=bind) = nops(bind) then RETURN(0) ; fi; lp2 := A007814(n) ; if lp2 = 0 then A144789(floor(n/2)) ; else lp2sh := A144789(n/2^lp2) ; if lp2sh = 0 then lp2 ; else min(lp2,lp2sh) ; fi; fi; end: for n from 1 to 140 do printf("%d,",A144789(n)) ; od: # _R. J. Mathar_, Sep 29 2008
%t A144789 Table[Min[Length/@Select[Split[IntegerDigits[n,2]],MemberQ[#,0]&]],{n,120}]/.\[Infinity]->0 (* _Harvey P. Dale_, Jul 24 2016 *)
%Y A144789 Cf. A087117, A144790.
%K A144789 base,nonn
%O A144789 1,4
%A A144789 _Leroy Quet_, Sep 21 2008
%E A144789 Extended by _R. J. Mathar_, Sep 29 2008