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A107814
a(1) = prime(14), for n >= 2, a(n) is the smallest prime not previously used which contains a digit from a(n-1).
28
43, 3, 13, 11, 17, 7, 37, 23, 2, 29, 19, 31, 41, 47, 67, 61, 71, 73, 53, 5, 59, 79, 89, 83, 103, 101, 107, 97, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277
OFFSET
1,1
COMMENTS
a(n) = prime(n) for almost all n. Probably a(n) = prime(n) for all n > N for some N, but N must be very large. - Charles R Greathouse IV, Jul 20 2011
LINKS
FORMULA
a(n) ~ n log n. - Charles R Greathouse IV, Jul 20 2011
MAPLE
Cands:= subsop(14=NULL, [seq(ithprime(i), i=1..1000)]):
S:= map(t -> convert(convert(t, base, 10), set), Cands):
R:= 43: x:= 43: xs:= {3, 4}:
for n from 2 to 100 do
found:= false;
for i from 1 do
if S[i] intersect xs <> {} then
R:= R, Cands[i];
x:= Cands[i];
xs:= S[i];
Cands:= subsop(i=NULL, Cands);
S:= subsop(i=NULL, S);
found:= true;
break
fi
od;
if not found then break fi;
od:
R; # Robert Israel, Dec 16 2024
MATHEMATICA
p=Prime[14]; b={p}; d=p; Do[Do[r=Prime[c]; If[FreeQ[b, r]&&Intersection@@IntegerDigits/@{d, r}=!={}, b=Append[b, r]; d=r; Break[]], {c, 1000}], {k, 60}]; b
CROSSREFS
Cf. A107353.
Other cases of seed: A107801 (a(1) = 2), A107802 (a(1) = 3), A107803 (a(1) = 5), A107804 (a(1) = 7), A107805 (a(1) = 11), A107806 (a(1) = 13), A107807 (a(1) = 17), A107808 (a(1) = 19), A107809 (a(1) = 23), A107810 (a(1) = 29), A107811 (a(1) = 31), A107812 (a(1) = 37), A107813 (a(1) = 41).
Sequence in context: A036202 A212316 A292996 * A093762 A354085 A156677
KEYWORD
nonn,base
AUTHOR
Zak Seidov and Eric Angelini, May 24 2005
STATUS
approved