OFFSET
1,1
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..10000 (first 220 terms from Robert Price)
MAPLE
b:= proc(n) option remember; `if`(n=1, 1, (l->
parse(cat(seq(`if`(l[i, 2]=1, l[i, 1], [l[i, 1],
l[i, 2]][]), i=1..nops(l)))))(sort(ifactors(n)[2])))
end:
a:= proc(n) option remember; local k; for k from
`if`(n=1, 0, a(n-1))+1 while b(k)>=k do od; k
end:
seq(a(n), n=1..100); # Alois P. Heinz, Mar 17 2020
MATHEMATICA
Select[Range[3712], A080670[[#]] < # &] (* Robert Price, Mar 17 2020 *)
PROG
(PARI) is(n, f=factor(n))=eval(concat(vector(#f~, i, if(f[i, 2]==1, Str(f[i, 1]), Str(f[i, 1], f[i, 2])))))<n \\ Charles R Greathouse IV, Mar 18 2020
CROSSREFS
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Sep 15 2011
STATUS
approved