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.
lim = 10^5; k1 = 0; k3 = 0; t = Table[{p = Prime[k], If[Mod[p, 4] == 1, ++k1, k1], If[Mod[p, 4] == 3, ++k3, k3]}, {k, 2, lim}]; A007350 = {3}; Do[ If[t[[k-1, 2]] < t[[k-1, 3]] && t[[k, 2]] == t[[k, 3]] && t[[k+1, 2]] > t[[k+1, 3]] || t[[k-1, 2]] > t[[k-1, 3]] && t[[k, 2]] == t[[k, 3]] && t[[k+1, 2]] < t[[k+1, 3]], AppendTo[A007350, t[[k+1, 1]]]], {k, 2, Length[t]-1}]; A007350 (* Jean-François Alcover, Sep 07 2011 *)
lim = 10^5; k1 = 0; k3 = 0; p = 2; t = {}; parity = Mod[p, 4]; Do[p = NextPrime[p]; If[Mod[p, 4] == 1, k1++, k3++]; If[(k1 - k3)*(parity - Mod[p, 4]) > 0, AppendTo[t, p]; parity = Mod[p, 4]], {lim}]; t (* T. D. Noe, Sep 07 2011 *)
primerace(mod,limit)={my(v=vector(mod), vm=0, ivm=0, imv); forprime(p=2, limit, my(m=p%mod); v[m+1]++; v[m+1]++; my(mv=vecmax(v, &imv)); if(mv>vm, if(imv!=ivm, print1(p, ", "); ivm=imv); vm=mv))};
primerace(7,8600) \\ Hugo Pfoertner, Jul 25 2021
X:= Vector(4): X[2]:= 1: m:= 3: p:= 3: count:= 1: R:= 2:
for i from 2 while count < 100 do
p:= nextprime(p);
j:= ((p mod 8)+1)/2;
X[j]:= X[j]+1;
mp:= max[index](X);
if mp <> m and X[mp] > X[m] then
m:= mp;
R:= R,p;
count:= count+1;
fi
od:
R; # Robert Israel, Nov 21 2024
V:= <(0$8)>:
lead:= 1:
Res:= NULL:
count:= 0:
p:= 1:
while count < 100 do
p:= nextprime(p);
t:= p mod 9;
V[t]:= V[t]+1;
if V[t] > V[lead] then
lead:= t;
Res:= Res, p;
count:= count+1;
fi
od:
Res; # Robert Israel, Jan 01 2018
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