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A097708
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Sum of prime-length repunits: Sum_{k=1..n} r(prime(k)), where r()=A002275.
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1
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0, 11, 122, 11233, 1122344, 11112233455, 1122223344566, 11112233334455677, 1122223344445566788, 11112233334455556677899, 11111122223344445566667789010, 1122222233334455556677778900121
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OFFSET
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0,2
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LINKS
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EXAMPLE
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a(3)=11233 because 11 + 111 + 11111 = 11233.
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PROG
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(PARI) a(n) = sum(k=1, n, (10^prime(k)-1)/9); \\ Michel Marcus, Jul 17 2022
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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STATUS
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approved
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