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Search: id:A089315
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| A089315 |
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Prime worms [successive digit differences with absolute value of 3]. |
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+0
5
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| 14741, 74747, 1414741, 1474141, 14141414141, 14141414741, 14141474741, 14147414741, 14147474141, 74141414147, 1474741414141, 7474141474747, 7474741414747, 14141474141414141, 14147414747474741, 14147474147474741
(list; graph; listen)
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OFFSET
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0,1
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COMMENT
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One of a family of prime worms differing according to the uniform absolute value of successive digit pairs. Sequence checked to 10^9.
This is a subset of A048400. Cf. A089291, A089316-A089317, A048398-A048405.
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REFERENCES
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Carlos Rivera's primepuzzles.net, Puzzle 246
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LINKS
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Carlos Rivera, Puzzle 246. The worm
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FORMULA
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Select prime numbers having the same first and last digits; if the uniform absolute value of successive digit differences is 3, add to sequence.
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EXAMPLE
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a(1)=74747 because the number is prime, has identical first and last digits, and abs(7-4)=3; abs(4-7)=3; abs(7-4)=3, and abs(4-7)=3. In this number, the worm is 7.
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CROSSREFS
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Sequence in context: A013861 A015312 A023333 this_sequence A015375 A043648 A035919
Adjacent sequences: A089312 A089313 A089314 this_sequence A089316 A089317 A089318
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KEYWORD
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easy,nonn
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AUTHOR
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Enoch Haga (Enokh(AT)comcast.net), Dec 25 2003
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EXTENSIONS
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More terms from David Wasserman (wasserma(AT)spawar.navy.mil), Sep 09 2005
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