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Numbers for which the "describe what you see" transform A045918 produces a prime.
2

%I #15 Dec 04 2020 10:39:04

%S 1,3,7,9,17,23,27,33,39,51,63,69,81,93,99,111,113,121,127,133,137,161,

%T 193,199,203,209,223,233,271,299,301,311,313,323,331,343,359,361,367,

%U 371,373,377,431,433,439,441,447,451,463,469,477,479,481,497

%N Numbers for which the "describe what you see" transform A045918 produces a prime.

%e E.g. 33 -> "Two threes" -> 23, which is prime.

%o (PARI) for(n=1,999,isprime(A045918(n)) & print1(n",")) \\ _M. F. Hasler_, Jan 27 2012

%Y Cf. A036979, A045918.

%K nonn,base,easy

%O 1,2

%A _G. L. Honaker, Jr._

%E Corrected by inserting the missing a(19)=127 by _M. F. Hasler_, Jan 27 2012