ec exponents in position 9n
a(9)=36
a(18)=1323
a(27)=69660
a(36)=360787
pg(36), pg(1323) and pg(69660) and pg(360787) are primes
a(9) is the 9th exponent leading to a ec prime
a(18) the 18th
a(27) the 27th
a(36) the 36th
36,1323,69660 and 360787 are divisible by a perfect square
36 and 69660 (even) are divisible by a square which is a 3 smooth number (infact 36 is divisible by 36 which is 3 smooth, 69660 is divisible by 18^2 whcih is 3 smooth)
1323 and 360787 (odd) are divisible by 21^2 and by 7^2 which are squares that are 7smooth numbers
so 36,1323,69660, 360787 are divisible either by 3^2*6^2 or by 3^2*7^2 or by 6^2 or by 7^2
360787 (mod (14^3)) is 1323
36 and 69660 even are of the form 8k+4
1323 and 360787 (odd) are of the form 8k+3
Last fiddled with by enzocreti on 20200827 at 09:48
