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Search: id:A090276
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| A090276 |
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Least number with identical digits such that the concatenation a(n) a(n-1) ...a(2)a(1) a(2) ... a(n-1) a(n) is a prime. |
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+0
2
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| 2, 7, 3, 33, 9, 77, 33, 999, 1111111, 3, 33, 777777, 111111111, 77, 333333, 111, 99999999, 3333333333, 777777, 1, 33333333333333333333, 999999999999999999999999999999999999, 99999999, 999999999999999999999999999999999999999999, 3333333333333333333333333
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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The resulting primes are given in A090275.
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EXAMPLE
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2,727,37273,... etc. are primes.
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CROSSREFS
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Cf. A090275.
Adjacent sequences: A090273 A090274 A090275 this_sequence A090277 A090278 A090279
Sequence in context: A089124 A117809 A052091 this_sequence A090564 A079072 A004584
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KEYWORD
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base,nonn
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Nov 28 2003
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EXTENSIONS
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More terms from Sam Alexander (amnalexander(AT)yahoo.com), Jan 06 2005
Many further terms from David Wasserman (wasserma(AT)spawar.navy.mil), Oct 27 2005
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