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 A107612 Primes with digital product = 2. 15
 2, 211, 2111, 111121, 111211, 112111, 1111211, 1111111121, 1111211111, 1121111111, 111111211111, 111211111111, 2111111111111, 111111111111112111, 111111112111111111, 111111211111111111, 112111111111111111 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Corresponding indices of primes in A107611. Cf. A053666, A101987. LINKS Harvey P. Dale, Table of n, a(n) for n = 1..684 FORMULA A107612(n) = prime(A107611(n)). MAPLE for i from 0 to 30 do it:=sum(10^j, j=0..i): for k from 0 to i do if isprime(it+10^k) then printf(`%d, `, it+10^k) fi: od:od: (Sellers) MATHEMATICA Flatten[ Table[ Select[ Sort[ FromDigits /@ Permutations[ Flatten[{2, Table[1, {n}]}]]], PrimeQ[ # ] &], {n, 0, 19}]] (* Robert G. Wilson v, May 19 2005 *) Select[Flatten[Table[FromDigits/@Permutations[PadRight[{2}, n, 1]], {n, 20}]], PrimeQ]//Sort (* Harvey P. Dale, May 28 2017 *) CROSSREFS Cf. A053666, A101987, A107611. Cf. A004022, A107689, A107690, A107691, A107692, A107693, A107694, A107695, A107696, A107697, A107698. Sequence in context: A167838 A106100 A167839 * A068814 A215641 A195335 Adjacent sequences:  A107609 A107610 A107611 * A107613 A107614 A107615 KEYWORD base,nonn AUTHOR Zak Seidov, May 17 2005 EXTENSIONS More terms from Robert G. Wilson v and James A. Sellers, May 19 2005 STATUS approved

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Last modified September 29 18:27 EDT 2020. Contains 337432 sequences. (Running on oeis4.)