OFFSET
1,2
COMMENTS
cf. A049345 n written in primorial base [Places reading from right have values (1, 2, 6, 30, 210, ...) = primorials]. Primes in this sequence are a(2) = 11, a(6) = 163, a(33) = 10337.
EXAMPLE
a(1) = A049345(1) = 1.
a(4) = 1 + 10 + 11 + 20 = 42.
a(5) = 1 + 10 + 11 + 20 + 21 = 63.
a(6) = 1 + 10 + 11 + 20 + 21 + 100 = 163.
a(33) = 1 + 10 + 11 + 20 + 21 + 100 + 101 + 110 + 111 + 120 + 121 + 200 + 201 + 210 + 211 + 220 + 221 + 300 + 301 + 310 + 311 + 320 + 321 + 400 + 401 + 410 + 411 + 420 + 421 + 1000 + 1001 + 1010 + 1011 = 10337.
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Jonathan Vos Post, Sep 20 2006
STATUS
approved