A238256 A060308 begins with one 2, one 3, one 5, two 7's, one 11, two 13's, i.e., d(n) = 1, 1, 1, 2, 1, 2, 1, 2, 3, 1,... times the primes (A000040). a(n) uses this distribution with noncomposites (A008578).

1, 2, 3, 5, 5, 7, 11, 11, 13, 17, 17, 19, 19, 19, 23, 29, 29, 29, 31, 31, 37, 41, 41, 43, 43, 43, 47, 47, 47, 53, 59, 59, 59, 61, 61, 67, 71, 71, 71, 73, 73, 79, 79, 79, 83, 83, 83, 83, 89, 89, 97, 101, 101, 103, 107, 107, 109, 109, 109, 109, 109, 109, 109

Offset: 1

Author

Paul Curtz, Mar 10 2014

Keywords

• nonn

Links

• Paul Curtz, Table of n, a(n) for n = 1..63

Crossrefs

Cf. A224911.

Programs

PARI

lista(nn) = {nn = nn\2; v = vector(nn, i, precprime(2*i)); vnc = concat(1, vector(nn, i, prime(i))); nv = vector(1, i, vnc[i]); ivnc = 1; for (i=2, #v, if (v[i] == v[i-1], nv = concat(nv, nv[#nv]), ivnc++; nv = concat(nv, vnc[ivnc]));); for (i=1, #nv, print1(nv[i], ", "));} \\ Michel Marcus, Mar 20 2014

Formula

Conjecture: a(n) is the greatest noncomposite (A008578) dividing A238691(n-1).