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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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1
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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; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| The resulting primes are given in A090275.
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EXAMPLE
| 2,727,37273,... etc. are primes.
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CROSSREFS
| Cf. A090275.
Sequence in context: A089124 A117809 A052091 * A090564 A079072 A004584
Adjacent sequences: A090273 A090274 A090275 * A090277 A090278 A090279
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KEYWORD
| base,nonn
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Nov 28 2003
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EXTENSIONS
| 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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