A371730 Indices of records in A371729: numbers k with A371729(k) > A371729(m) for all m < k.

2, 5, 9, 13, 17, 25, 37, 41, 49, 73, 97, 109, 161, 181, 289, 307, 361, 433, 529, 701, 841, 881, 961, 1189, 1369, 1681, 1849, 2209, 2393, 2449, 3277, 3457, 3781, 4096, 4159, 4841, 4861, 5741, 5851, 6049, 7921, 10201, 11449, 11881, 15049, 15401, 19601, 27026, 32768

Offset

1,1

Comments

The corresponding record values are 0, 1, 2, 3, 4, 5, 7, 8, 9, 11, 12, ... (see the link for more values).

Links

Amiram Eldar, Table of n, a(n) for n = 1..69 (terms below 10^6)

Amiram Eldar, Table of n, a(n), A371729(a(n)) for n = 1..69.

Wikipedia, Pseudoprime.

Index entries for sequences related to pseudoprimes.

Mathematica

f[k_] := Count[Range[4, k - 1], _?(CompositeQ[#] && PowerMod[k, # - 1, #] == 1 &)]; seq[kmax_] := Module[{s = {}, fm = -1, f1}, Do[f1 = f[k]; If[f1 > fm, fm = f1; AppendTo[s, k]], {k, 2, kmax}]; s]; seq[2500]

Prog

(PARI) f(n) = {my(c=0); forcomposite(k = 4, n-1, if(Mod(n, k)^(k-1) == 1, c++)); c; }
lista(kmax) = {my(fm = -1, f1); for(k = 2, kmax, f1 = f(k); if(f1 > fm, fm = f1; print1(k, ", "))); }

Crossrefs

Cf. A371729.

Sequence in context: A353036 A182814 A351628 * A055025 A178805 A088907

Adjacent sequences: A371726 A371727 A371729 * A371731 A371732 A371733

Keyword

nonn

Author

Amiram Eldar, Apr 05 2024

Status

approved