

A224730


Smallest prime q such that 2n+1 = p^3  2q for some odd prime p, or 0 if no such prime exists.


4



61, 11, 59, 167, 1093, 7, 1091, 5, 53, 3, 2, 653, 0, 157, 47, 3413, 25309, 647, 43, 151, 41, 149, 25303, 641, 37, 14869, 74411, 14867, 1069, 6053, 31, 139, 29, 137, 1063, 6047, 1061, 3391, 23, 131, 37309189, 51869, 19, 127, 17, 619, 1051, 617, 13, 39703, 11
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OFFSET

1,1


COMMENTS

See the conjecture and the comments in A185046, and the corresponding primes p.


LINKS

Michel Lagneau, Table of n, a(n) for n = 1..10000


EXAMPLE

a(4) = 167 because, for (p, q) = (7, 167), 9 = 7^3  2*167 = 343  334 = 9.


MAPLE

for n from 3 by 2 to 200 do:
jj:=0:
for j from 1 to 10000 while (jj=0) do:
p:=ithprime(j):q:=(p^3n)/2:
if q> 0 and type(q, prime)=true
then
jj:=1:printf(`%d, `, q):
else
fi:
od:
if jj=0 then
printf(`%d, `, 0):
else
fi:
od:


CROSSREFS

Cf. A185046.
Sequence in context: A077331 A106426 A106416 * A248143 A012860 A002108
Adjacent sequences: A224727 A224728 A224729 * A224731 A224732 A224733


KEYWORD

nonn


AUTHOR

Michel Lagneau, Apr 17 2013


STATUS

approved



