A054507 Log_b 4 where b is smallest primitive root (A001918) mod n-th prime.

2, 4, 2, 2, 12, 2, 4, 2, 18, 2, 12, 12, 36, 2, 2, 2, 2, 12, 16, 8, 2, 32, 68, 2, 88, 2, 6, 24, 18, 2, 20, 2, 2, 140, 126, 2, 80, 2, 2, 2, 88, 68, 2, 14, 2, 138, 2, 42, 144, 132, 140, 220, 96, 118, 2, 38, 18, 128, 36, 2, 186, 44, 236, 2, 242, 272, 2, 2, 328, 270, 218, 2, 2, 268, 2

Offset: 3

Author

N. J. A. Sloane, Apr 09 2000

Keywords

• nonn
• easy

References

• Tom M. Apostol, Introduction to Analytic Number Theory, Springer-Verlag, 1976, Table 10.2, pp. 216-217.

Links

• Amiram Eldar, Table of n, a(n) for n = 3..10000

Crossrefs

Cf. table in A054503.

Cf. A001918, A054505, A054506, A054508, A054509, A054510, A054511, A054512, A054513.

Programs

Mathematica

a[n_] := Module[{p, b, lg = 1}, b = PrimitiveRoot[p = Prime[n]]; While[ PowerMod[b, lg, p] != 4, lg++]; lg]; Array[a, 100, 3] (* Jean-François Alcover, Sep 03 2016 *)

Extensions

More terms from James Sellers, Apr 09 2000