A097708 Sum of prime-length repunits: Sum_{k=1..n} r(prime(k)), where r()=A002275.
0, 11, 122, 11233, 1122344, 11112233455, 1122223344566, 11112233334455677, 1122223344445566788, 11112233334455556677899, 11111122223344445566667789010, 1122222233334455556677778900121
Offset: 0
Examples
a(3)=11233 because 11 + 111 + 11111 = 11233.
Programs
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PARI
a(n) = sum(k=1, n, (10^prime(k)-1)/9); \\ Michel Marcus, Jul 17 2022