0,1

The sum of the reciprocals of the terms appears to converge.

(PARI) triprimes(n) = { sr = 0; for(j=1, n, x = j*(j+1)/2+2; z = prime(x); sr+=1.0/z; print1(z" "); ); print(); print(sr); }

Apart from initial term, primes in second diagonal of triangle in A078721.

Sequence in context: A127453 A092602 A134127 this_sequence A089098 A129384 A131887

Adjacent sequences: A078719 A078720 A078721 this_sequence A078723 A078724 A078725

easy,nonn

Cino Hilliard (hillcino368(AT)gmail.com), Dec 20 2002