|
|
A124924
|
|
Primes p such that p^2 divides A124923((3p-1)/2) = ((3p-1)/2)^(3(p-1)/2) + 1.
|
|
2
|
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
Also, primes p such that (-2)^((p-1)/2) == -1-3p/2 (mod p^2).
No other terms below 10^11.
|
|
LINKS
|
|
|
EXAMPLE
|
5 is in this sequence because A124923((3*5-1)/2) = A124923(7) = 7^8 + 1 = 117650 is divisible by 5^2 = 25.
|
|
MATHEMATICA
|
Do[ p = Prime[n]; m = (3p-1)/2; f = PowerMod[ m, m-1, p^2 ] + 1; If[ IntegerQ[ f/p^2 ], Print[p] ], {n, 2, 10000} ]
|
|
CROSSREFS
|
|
|
KEYWORD
|
hard,more,nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|