[seqfan] Generalizing Dirichlet, new sequences.

[rkg]

I didn't find 13, 37, 157, 541, 877, ... in OEIS.
It is a subseq of A068228 = A141122. Nor did I find
12, 36, 156, 540, 876, ... These are the values of n
for which n+1 is prime, n+2 is twice a prime and
n+3 is thrice a prime.  The former sequence is
primes p such that p+1 is twice a prime and p+2 is
thrice a prime.  Presumably infinite, though I
don't know what generalizations there are for
Dirichlet's theorem on primes in arithmetic prograssions.

I'm skating on thin ice -- see A045753, A002822.  R.