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A261965
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Minimal appendage-sequence of primes with seed 1, base 10, and appendages of the form 0s(n); see Comments.
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2
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1, 101, 10103, 10103011, 10103011013, 1010301101309, 10103011013090003, 101030110130900030009, 10103011013090003000903, 1010301101309000300090303, 1010301101309000300090303009, 1010301101309000300090303009059, 1010301101309000300090303009059061
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OFFSET
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1,2
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COMMENTS
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The minimal appendage-sequence of primes with seed s and base b is defined as follows:
a(1) = s
a(2) = least prime that begins with s0;
a(3) = least prime that begins with a(2)0;
a(n) = least prime that begins with a(n-1)0.
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LINKS
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EXAMPLE
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11 comes from a(3) = 10103 by appending 011 to a(3); the result is the least prime that begins with 10103. Triangular format:
1
101
10103
10103011
10103011013
1010301101309
10103011013090003
101030110130900030009
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MATHEMATICA
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base = 10; s = {{1}}; Do[NestWhile[# + 1 &, 1, (nn = #; ! PrimeQ[FromDigits[tmp=IntegerDigits[FromDigits[Flatten[IntegerDigits[Join[Last[s], {0}, IntegerDigits[nn - Sum[base^n, {n, l = NestWhile[# + 1 &, 1, ! (nn - (Sum[base^n, {n, #}]) < 0) &] - 1}], base, l + 1]]]]]], base]]) &]; AppendTo[s, {FromDigits[tmp]}], {20}];
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CROSSREFS
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KEYWORD
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nonn,easy,base
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AUTHOR
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STATUS
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approved
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