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A093100
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"Lucas-digits": start with "13", append sum of first 2 digits to the preceding number, drop first digit.
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1
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13, 34, 47, 711, 118, 182, 829, 2910, 91011, 101110, 11101, 11012, 10122, 1221, 2213, 2134, 1343, 3434, 4347, 3477, 4777, 77711, 771114, 7111414, 1114148, 1141482, 1414822, 4148225, 1482255, 4822555, 82255512, 225551210, 255512104, 555121047
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OFFSET
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1,1
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COMMENTS
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There are only 7 primes in the first 1000 terms of this sequence. The first 6 primes are 13, 47, 829, 2213, 77711, and 174111811681183993. The 7th prime, a(920), has 214 digits. - Harvey P. Dale, Aug 04 2014
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LINKS
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EXAMPLE
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a(4): sum of first 2 digits of a(3)=11, append 11 to 47 and get 4711, drop first digit and get 711.
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MATHEMATICA
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ld[n_]:=Module[{idn=IntegerDigits[n]}, FromDigits[Rest[Join[ idn, IntegerDigits[ Total[ Take[idn, 2]]]]]]]; NestList[ld, 13, 40] (* Harvey P. Dale, Aug 04 2014 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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