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A089702 a(1) = 2 then primes in nondecreasing order such that every concatenation is prime. 1
2, 3, 3, 3, 3, 23, 43, 59, 67, 83, 199, 239, 421, 569, 613, 1307, 2017, 2129, 2467, 2741, 2953, 3011, 3319, 3413, 3607, 3617, 5449, 6917, 7333, 7529, 8389, 10211, 10357, 12641, 12703, 15077, 17107, 21341, 21799, 22469, 32911, 33587, 33613, 33647 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
LINKS
EXAMPLE
2,23,233,2333,23333,2333323 etc. are primes.
MAPLE
ds:=proc(s) local j: RETURN(add(s[j]*10^(j-1), j=1..nops(s))):end: a:=[2]: k:=1: for n from 1 to 50 do l:=nops(a): for i from k do p:=ithprime(i): if isprime(ds([op(convert(p, base, 10)), seq(op(convert(a[l-j], base, 10)), j=0..l-1)])) then a:=[op(a), p]: k:=i: break fi od od: op(a); # C. Ronaldo
CROSSREFS
Cf. A089703.
Sequence in context: A069603 A033679 A051670 * A089336 A089335 A088093
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Nov 10 2003
EXTENSIONS
More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Dec 25 2004
STATUS
approved

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Last modified July 22 07:42 EDT 2024. Contains 374481 sequences. (Running on oeis4.)