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Search: id:A110028
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| A110028 |
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Primes with a prime number of digits, all of them prime, that add up to a prime. |
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+0
2
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| 23, 223, 227, 337, 353, 373, 557, 577, 733, 757, 773, 22573, 23327, 25237, 25253, 25523, 27253, 27527, 32233, 32237, 32257, 32323, 32327, 33223, 33353, 33377, 33533, 33773, 35227, 35353, 35533, 35537, 35573, 35753, 37223, 37337, 52237
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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First 7 digit number in this sequence is 2222333
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EXAMPLE
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E.g. "a(12)=22573 because 22573 is prime, it has five digits (5 is a prime), all digits (2,3,5,7) are prime and also the sum of the digits is 2+2+5+7+3=19 which is also a prime"
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MAPLE
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a:=proc(n) local nn: nn:=convert(n, base, 10): if isprime(n)=true and isprime(nops(nn))=true and map(isprime, nn)=[seq(true, i=1..nops(nn))] and isprime(add(nn[j], j=1..nops(nn)))=true then n else fi end: seq(a(k), k=1..60000); - Emeric Deutsch (deutsch(AT)duke.poly.edu), Apr 02 2006
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CROSSREFS
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Cf. A000040, A062088.
Sequence in context: A142374 A112747 A027481 this_sequence A117608 A038514 A125386
Adjacent sequences: A110025 A110026 A110027 this_sequence A110029 A110030 A110031
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KEYWORD
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nonn,base
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AUTHOR
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Sergio Pimentel (ferdiego(AT)cox.net), Mar 31 2006
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