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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 (list; graph; refs; listen; history; text; internal format)
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^3-n)/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

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Last modified December 4 10:32 EST 2022. Contains 358556 sequences. (Running on oeis4.)