This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A002225 M5224 N2274 #40 Apr 11 2024 10:10:54 %S A002225 31,307,643,5113,21787,39199,360007,360007,4775569,10318249,10318249, %T A002225 65139031,387453811,913900417,2278522747,2741702809,25147657981, %U A002225 118748663779,156776294593,747206701687,1151810360731,1151810360731,1151810360731 %N A002225 a(n) is the smallest prime p such that each of the first n primes has three cube roots mod p. %C A002225 a(n) is the smallest prime p == 1 (mod 3) such that each of the first n primes is a cubic residue mod p. - _Robert Israel_, Aug 02 2016 %D A002225 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A002225 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A002225 A. E. Western and J. C. P. Miller, Tables of Indices and Primitive Roots. Royal Society Mathematical Tables, Vol. 9, Cambridge Univ. Press, 1968, p. XVI. %H A002225 A. E. Western and J. C. P. Miller, <a href="/A002223/a002223.pdf">Tables of Indices and Primitive Roots</a>, Royal Society Mathematical Tables, Vol. 9, Cambridge Univ. Press, 1968 [Annotated scans of selected pages] %e A002225 For n = 2, the first two primes 2 and 3 each have three cube roots mod 307: 2 has cube roots 52, 270, 292 and 3 has cube roots 192, 194, 228. - _Robert Israel_, Aug 02 2016 %p A002225 Primes:= [2]: pp:= 7: %p A002225 for n from 1 to 12 do %p A002225 for p from pp by 6 while %p A002225 not(isprime(p) and andmap(t -> t &^ ((p-1)/3) mod p = 1, Primes)) %p A002225 do od: %p A002225 A[n]:= p; %p A002225 pp:= p; %p A002225 Primes:= [op(Primes), nextprime(Primes[-1])]; %p A002225 od: %p A002225 seq(A[i],i=1..12); # _Robert Israel_, Aug 02 2016 %t A002225 (* This naive program being very slow, limit is set to 8 terms *) lim=8; np[] := While[p=NextPrime[p]; Mod[p,3]!=1]; crQ[n_, p_] := Reduce[ 0<x<p && Mod[x^3, p]==n, x, Integers]=!=False; p=2; pp={p}; A002225={}; While[Length[A002225] < lim, If[And @@ (crQ[#,p]& /@ pp), AppendTo[pp, NextPrime[ Last[pp]]]; Print[p]; AppendTo[A002225,p], np[] ] ]; A002225 (* _Jean-François Alcover_, Sep 09 2011 *) %Y A002225 Smallest prime p such that each of the first n primes has q q-th roots mod p: A147972 (q=2), this sequence (q=3), A002226 (q=5), A002227 (q=7), A002228 (q=11), A060363 (q=13), A060364 (q=17). %Y A002225 Cf. A002223, A002224. %Y A002225 Subset of A014752. Except for a(1), subset of A014753. Except for a(1) and a(2), subset of A040044. %K A002225 nonn,nice,more %O A002225 1,1 %A A002225 _N. J. A. Sloane_ %E A002225 More terms from _Don Reble_, Oct 09 2001 %E A002225 Name corrected by _Robert Israel_, Aug 02 2016 %E A002225 a(18)-a(23) from _Sergey Paramonov_, Apr 11 2024