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A329121
Smallest k such that m//A002275(n)//m is prime, where // denotes concatenation, A002275(n) is the n-th repunit (R_n) and m = k+10^(A006519(n)-1).
1
0, 2, 3, 16, 73, 18, 7, 28, 117, 72, 7, 2, 7, 2, 33, 10, 29, 0, 21, 10, 191, 0, 1133, 30, 79, 20, 81, 58, 19, 2, 57, 116, 77, 108, 79, 48, 97, 40, 1043, 42, 47, 86, 13, 52, 149, 82, 47, 56, 9, 80, 41, 42, 61, 86, 51, 68, 311, 262, 1001, 222, 7, 496, 1367, 12
OFFSET
0,2
COMMENTS
a(n) = A263182(n) - 10^(A006519(n)-1). We use the convention that A007814(0) = 0 and A006519(0) = 1.
a(A004023(n)-2) = 0.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Chai Wah Wu, Nov 05 2019
STATUS
approved