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A051247
Binary numbers d(1)...d(j) such that d(i) = d(j+1-i) for all but 4 values of i.
4
10, 12, 18, 22, 24, 28, 34, 36, 39, 40, 43, 46, 48, 53, 54, 57, 58, 60, 66, 68, 71, 74, 76, 79, 80, 83, 86, 88, 91, 94, 96, 101, 102, 104, 109, 110, 113, 114, 116, 121, 122, 124, 130, 132, 135, 136, 139, 141, 144, 147, 149, 154, 156
OFFSET
1,1
COMMENTS
Each number becomes a palindrome by changing two digits.
LINKS
MAPLE
filter:= proc(n) local L;
L:= convert(n, base, 2):
nops(select(i -> L[i] = L[-i], [$1..nops(L)]))=nops(L)-4
end proc:
select(filter, [$1..1000]); # Robert Israel, Nov 10 2024
CROSSREFS
Sequence in context: A129120 A134516 A144363 * A242335 A050579 A255845
KEYWORD
nonn,base,changed
EXTENSIONS
Name corrected by Sean A. Irvine, Aug 20 2021
Name corrected by Robert Israel, Nov 10 2024
STATUS
approved