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A306785
Primes p such that p^2 divides A050443(p).
1
OFFSET
1,1
COMMENTS
A050443(p) is divisible by p for p prime, so sequence looks for primes p such that p^2 divides A050443(p).
No more terms < 10^11. - Lucas A. Brown, Jan 27 2021
EXAMPLE
A050443(2) = 0 is divisible by 2^2.
A050443(5) = 0 is divisible by 5^2.
A050443(1051) is divisible by 1051^2.
PROG
(PARI) M = [0, 1, 0, 0; 0, 0, 1, 0; 0, 0, 0, 1; 1, 1, 0, 0];
b(n) = lift( ( Mod(M, n^2)^n * [4, 0, 0, 3]~)[1] ); \\ A050443(n) mod n^2
forprime(n=2, 10^10, if( b(n)==0, print1(n, ", ") ) ); \\ Joerg Arndt, Mar 11 2019
CROSSREFS
KEYWORD
nonn,more,bref
AUTHOR
Seiichi Manyama, Mar 09 2019
STATUS
approved