cp's OEIS Frontend

A051246 Binary numbers d(1)...d(j) such that d(i) != d(j+1-i) for all but 4 values of i.

%I A051246 #13 Nov 10 2024 09:24:58
%S A051246 9,15,32,35,37,41,44,47,49,50,55,59,61,62,130,132,135,136,139,141,144,
%T A051246 147,149,154,156,159,160,163,166,169,172,175,177,180,183,184,187,190,
%U A051246 192,197,198,201,202,207,209,210,215,216,221
%N A051246 Binary numbers d(1)...d(j) such that d(i) != d(j+1-i) for all but 4 values of i.
%H A051246 Robert Israel, <a href="/A051246/b051246.txt">Table of n, a(n) for n = 1..10000</a>
%p A051246 filter:= proc(n) local L;
%p A051246   L:= convert(n,base,2):
%p A051246   nops(select(i -> L[i] = L[-i], [$1..nops(L)]))=4
%p A051246 end proc:
%p A051246 select(filter, [$1..1000]); # _Robert Israel_, Nov 10 2024
%Y A051246 Cf. A051245, A051247, A050875.
%K A051246 nonn,base
%O A051246 1,1
%A A051246 _Clark Kimberling_
%E A051246 Name corrected by _Sean A. Irvine_, Aug 20 2021
%E A051246 Name corrected by _Robert Israel_, Nov 10 2024