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A239716
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Primes of the form m = 6^i + 6^j - 1, where i > j >= 0.
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1
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41, 251, 1301, 1511, 46691, 47951, 279941, 1679831, 10077911, 10124351, 60466181, 60466391, 60473951, 362797091, 362797271, 362843711, 2176782371, 2237248511, 13060694051, 13121160191, 78364164101, 78364164311, 78364171871
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OFFSET
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1,1
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COMMENTS
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The base-6 representation of a term 6^i + 6^j - 1 has base-6 digital sum = 1 + 5*j == 1 (mod 5).
In base-6 representation the first terms are 105, 1055, 10005, 10555, 1000055, 1005555, 10000005, 100000555, 1000000555, 1000555555, 10000000005, 10000000555,
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LINKS
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EXAMPLE
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a(1) = 41, since 41 = 6^2 + 6^1 - 1 is prime.
a(2) = 251, since 251 = 6^3 + 6^2 - 1 is prime.
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PROG
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(Smalltalk)
"Answers an array of the first n terms of A239716.
Uses method primesWhichAreDistinctPowersOf: b withOffset: d from A239712.
Answer: #(41 241 ... ) [a(1) ... a(n)]"
^self primesWhichAreDistinctPowersOf: 6 withOffset: -1
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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