editing
approved
editing
approved
editing
proposed
reviewed
approved
proposed
reviewed
editing
proposed
Michel Lagneau, <a href="/A248746/b248746.txt">Table of n, a(n) for n = 1..5000</a>
allocated for Michel Lagneaua(n) is the index k of the greatest prime divisor A002313(k) of n^2+1.
1, 2, 2, 4, 3, 6, 2, 3, 7, 13, 9, 5, 4, 22, 15, 26, 5, 3, 20, 39, 4, 12, 8, 51, 31, 60, 10, 18, 41, 8, 6, 7, 14, 11, 54, 105, 16, 4, 65, 121, 5, 35, 6, 17, 83, 10, 4, 45, 97, 9, 106, 48, 29, 209, 11, 221, 3, 59, 133, 28, 138, 66, 38, 25, 155, 294, 43, 6, 174, 5
1,2
with(numtheory):T:=array(1..50000):T[1]:=2:kk:=1:nn:=10^5:
for i from 1 to nn do:
p:=4*i+1:
if type(p, prime)=true
then
kk:=kk+1:T[kk]:=p:
else
fi:
od:
for k from 1 to 5000 do:ii:=0:
y:=factorset(k^2+1):n2:=nops(y):t:=y[n2]:
for l from 1 to kk while(ii=0)do :
if t=T[l]
then
printf(`%d, `, l):
else
fi:
od:
od:
allocated
nonn
Michel Lagneau, Oct 13 2014
approved
editing
allocated for Michel Lagneau
allocated
approved