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A073326
Smallest x such that prime(x) == n (mod (x-pi(x)-1)).
3
6, 67, 9, 10, 13, 96, 15, 16, 74, 73, 32, 85, 31, 4086, 228, 611, 28, 30, 44, 616, 263, 617, 43, 4090, 47, 633, 241, 631, 49, 122195143823, 48, 102, 123, 622, 62, 120, 65, 103, 112, 108, 64, 4094, 63, 127, 271, 109, 128, 129, 70, 132, 133, 137, 131, 4060, 644
OFFSET
1,1
FORMULA
a(n) = Min{x : A000040(x) == n (mod (x-A000720(x)-1)) }.
EXAMPLE
p(10) mod (10-PrimePi(10)-1) = 29 mod (10-4-1) = 29 mod 5 = 4 and a(4)=10.
MATHEMATICA
a[n_] := (k = 4; While[ Mod[ Prime[k], k - PrimePi[k] - 1] != n, k++ ]; k); Table[ a[n], {n, 1, 29}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Jul 30 2002
EXTENSIONS
Edited by Robert G. Wilson v, Jul 31 2002
a(30) from Giovanni Resta, Sep 02 2019
STATUS
approved