OFFSET
1,2
COMMENTS
a(19) > 1.3*10^11. - Robert G. Wilson v, Dec 17 2002
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..566 (terms < 10^57)
MATHEMATICA
NextOddNbr[n_] := Block[{d = If[ EvenQ[n], IntegerDigits[n + 1], IntegerDigits[n + 2]], l}, l = Length[d]; While[l != 1, If[ EvenQ[ d[[l]]], d[[l]]++ ]; If[d[[l]] > 9, d[[l - 1]]++; d[[l]] = 1]; l-- ]; If[ EvenQ[ d[[1]]], d[[1]]++ ]; If[ d[[1]] > 9, d[[1]] = 11]; FromDigits[d]] k = 1; Do[ If[ !PrimeQ[k] && Apply[GCD, Last[ Transpose[ FactorInteger[k]]]] > 1, Print[k]]; k = NextOddNbr[k], {n, 1, 10^8}]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Robert G. Wilson v and Zak Seidov, Oct 11 2002
EXTENSIONS
Extended by Robert G. Wilson v, Dec 17 2002
Terms a(19) and beyond from Giovanni Resta, Mar 13 2020
STATUS
approved