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A226429
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Number of numerical semigroups S of genus 3^n having a minimal generating set of cardinality 2.
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0
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2, 3, 4, 4, 5, 7, 8, 9, 8, 9, 11, 13, 11, 15, 16, 14, 14, 18, 20, 21
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OFFSET
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1,1
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LINKS
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FORMULA
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a(n) = n + 1 if 2*3^n - 1 is prime.
a(n) ~ n + 1.
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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