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A342699
Numbers k such that A342698(k) = k.
2
0, 1, 3, 7, 9, 12, 15, 17, 19, 24, 25, 28, 31, 33, 35, 39, 48, 49, 51, 56, 57, 60, 63, 65, 67, 71, 79, 96, 97, 99, 103, 112, 113, 115, 120, 121, 124, 127, 129, 131, 135, 143, 153, 159, 192, 193, 195, 199, 204, 207, 224, 225, 227, 231, 240, 241, 243, 248, 249
OFFSET
1,3
COMMENTS
Equivalently, these are the numbers k such that each bit in the binary representation of k is next to a bit with the same value (and we consider that the first bit is next to the last bit). Hence, all terms of A033015 belong to this sequence.
LINKS
PROG
(PARI) is(n) = my (w=#binary(n)); sum(k=0, w-1, ((bittest(n, (k-1)%w)+bittest(n, k%w)+bittest(n, (k+1)%w))>=2) * 2^k)==n
CROSSREFS
Sequence in context: A110404 A366529 A190366 * A284819 A190742 A289906
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Mar 18 2021
STATUS
approved