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A085709
a(0)=1; then smallest multiple of n such that a(n) + a(n-1) is a semiprime.
0
1, 3, 6, 3, 12, 10, 12, 14, 8, 18, 20, 66
OFFSET
0,2
EXAMPLE
a(12) does not exist, since 66+12k = 2*3*(2k+11) is not a semiprime for any positive k.
CROSSREFS
Cf. A001358.
Sequence in context: A336769 A337035 A203491 * A120910 A109044 A205844
KEYWORD
fini,full,nonn
AUTHOR
Jason Earls and Amarnath Murthy, Jul 19 2003
EXTENSIONS
Edited by Dean Hickerson, Jul 19 2003
STATUS
approved