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A056493
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Number of primitive (period n) periodic palindromes using a maximum of two different symbols.
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3
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2, 1, 2, 3, 6, 7, 14, 18, 28, 39, 62, 81, 126, 175, 246, 360, 510, 728, 1022, 1485, 2030, 3007, 4094, 6030, 8184, 12159, 16352, 24381, 32766, 48849, 65534, 97920, 131006, 196095, 262122, 392364, 524286, 785407, 1048446, 1571310, 2097150, 3143497
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| For example, aaabbb is not a (finite) palindrome but it is a periodic palindrome.
Also aperiodic necklaces (Lyndon words) that are the same when turned over.
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REFERENCES
| M. R. Nester (1999). Mathematical investigations of some plant interaction designs. PhD Thesis. University of Queensland, Brisbane, Australia.
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LINKS
| Index entries for sequences related to Lyndon words
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FORMULA
| Sum mu(d)*A029744(n/d) where d divides n.
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CROSSREFS
| Cf. A056458.
Sequence in context: A128474 A108618 A097719 * A001371 A001037 A122086
Adjacent sequences: A056490 A056491 A056492 * A056494 A056495 A056496
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KEYWORD
| nonn
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AUTHOR
| Marks R. Nester (nesterm(AT)dpi.qld.gov.au)
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EXTENSIONS
| More terms and additional comments from Christian G. Bower (bowerc(AT)usa.net), Jun 22 2000
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