1320061domain: NPropertiesPrimalityPrimeyesAppears in sequencesPrimes p equal to the sum in base 3 of the digits of all primes < p - digit-sum of the index of prime p(i-1).at n=28A241897Number of regions formed after n points have been placed in general position on each edge of a triangle (as in A365929).at n=28A367015Prime numbersat n=101438