OFFSET
1,1
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..10000
FORMULA
EXAMPLE
a(1) = 22 because "22" does indeed consist of "two 2's" and 22 = 2 * 11 is semiprime. a(4) = 10213223 because 10213223 consists of one "0", two 1's, three 2's, and two 3's; and 10213223 = 41 * 249103 is semiprime.
CROSSREFS
KEYWORD
nonn,base,fini,less
AUTHOR
Jonathan Vos Post, Feb 09 2010
EXTENSIONS
More terms from Giovanni Resta, Aug 14 2019
STATUS
approved