%I A089394
%S A089394 7,89,881,8821,80849,864883,8608081,48804809,608844043
%N A089394 Largest n-digit member of A089392.
%C A089394 A089392 has no members with 10, 11, or 12 digits. It is unlikely that
it has any with more than 12 digits. - David Wasserman (wasserma(AT)spawar.navy.mil),
Sep 15 2005
%p A089394 with(combinat): ds:=proc(s) local j: RETURN(add(s[j]*10^(j-1),j=1..nops(s))):end:
for d from 1 to 6 do sch:=[seq([1,op(i),d+1],i=[[],seq([j],j=2..d)])]:
for n from 10^d-1 by -1 to 10^(d-1) do sn:=convert(n,base,10): fl:=0:
for s in sch do m:=add(j,j=[seq(ds(sn[s[i]..s[i+1]-1]),i=1..nops(s)-1)]):
if not isprime(m) then fl:=1: break fi od: if fl=0 then printf("%d,
",n):break fi od od: (C. Ronaldo)
%Y A089394 Cf. A089392, A089393.
%Y A089394 Sequence in context: A036902 A142204 A071363 this_sequence A068692 A053302
A068877
%Y A089394 Adjacent sequences: A089391 A089392 A089393 this_sequence A089395 A089396
A089397
%K A089394 base,nonn
%O A089394 1,1
%A A089394 Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Nov 10 2003
%E A089394 More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Dec 25 2004
%E A089394 3 more terms from David Wasserman (wasserma(AT)spawar.navy.mil), Sep
15 2005
|