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A051246
Binary numbers d(1)...d(j) such that d(i) != d(j+1-i) for all but 4 values of i.
1
9, 15, 32, 35, 37, 41, 44, 47, 49, 50, 55, 59, 61, 62, 130, 132, 135, 136, 139, 141, 144, 147, 149, 154, 156, 159, 160, 163, 166, 169, 172, 175, 177, 180, 183, 184, 187, 190, 192, 197, 198, 201, 202, 207, 209, 210, 215, 216, 221
OFFSET
1,1
LINKS
MAPLE
filter:= proc(n) local L;
L:= convert(n, base, 2):
nops(select(i -> L[i] = L[-i], [$1..nops(L)]))=4
end proc:
select(filter, [$1..1000]); # Robert Israel, Nov 10 2024
CROSSREFS
KEYWORD
nonn,base,changed
EXTENSIONS
Name corrected by Sean A. Irvine, Aug 20 2021
Name corrected by Robert Israel, Nov 10 2024
STATUS
approved