A317249 Positions of records in A204911.

1, 4, 20, 28, 44, 101, 359, 667, 673, 821, 869, 1079, 2623, 3851, 4987, 5171, 9397, 18833

Offset

1,2

Links

Table of n, a(n) for n=1..18.

Example

a(1)=1 with A204911(1)=5.
a(2)=4 because A204911(4)=7 while A204911(k)<=5 for k<4.
a(3)=20 because A204911(20)=11 while A204911(k)<=7 for k<20.

Maple

f:= proc(n) local V, q, r;
  V:= Array(0..n-1); q:= 4;
  do
   q:= nextprime(q);
   r:= q mod n;
   if V[r] = 0 then V[r]:= q
   else return V[r]
   fi
  od
end proc:
Recs:= 1: r:= 5:
for n from 2 to 20000 do
  rn:= f(n);
  if rn > r then Recs:= Recs, n; r:= rn fi
od:
Recs;

Crossrefs

Cf. A204911, A317250.

Sequence in context: A198831 A323040 A259755 * A181433 A079454 A205670

Adjacent sequences: A317246 A317247 A317248 * A317250 A317251 A317252

Keyword

nonn,more

Author

Robert Israel, Jul 24 2018

Status

approved