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 A055019 Numbers n such that A051885(p_n) is prime, where p_n=A000040(n) is the n-th prime. 1
 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 20, 22, 25, 40, 41, 55, 57, 64, 77, 125, 663, 1053, 1414, 1711, 2822, 2956, 4107, 7463 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Numbers n such that A051885(A000040(n)) = A054750(n). No other terms below 10^4. LINKS EXAMPLE The 125th prime is 691. The least integer with sum of digits 691 is A051885(691) = 8*10^76-1 which is prime. This is the 22nd prime with this property, so a(22)=125. PROG (PARI) for(X=1, 300, a=prime(X)%9; b=prime(X)\9; m=(a+1)*10^b-1; if(isprime(m), print([X, prime(X), m]) ) ) CROSSREFS Cf. A054750, A051885. Sequence in context: A129511 A174905 A191849 * A172152 A218444 A014122 Adjacent sequences:  A055016 A055017 A055018 * A055020 A055021 A055022 KEYWORD more,nonn,base AUTHOR Kok Seng Chua (chuaks(AT)ihpc.nus.edu.sg), May 31 2000 EXTENSIONS More terms from Jason Earls (zevi_35711(AT)yahoo.com), Jun 22 2001 a(27)-a(30) from Max Alekseyev, Dec 09 2011 STATUS approved

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