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Primes that are in A070196.
1

%I #18 Jan 20 2024 09:24:58

%S 2,11,101,233,277,409,499,521,547,587,607,617,631,659,661,677,719,727,

%T 739,743,751,769,773,787,809,827,829,839,859,863,881,883,919,929,941,

%U 953,971,991,997,1009,1021,1031,1049,1051,1061,1063,1069,1087,1103,1109,1151,1163,1171,1181,1187,1193

%N Primes that are in A070196.

%C Primes p such that for some k, p = k + the sorted version of the base-10 digits of k.

%H Robert Israel, <a href="/A368879/b368879.txt">Table of n, a(n) for n = 1..10000</a>

%e a(4) = 233 is a term because 233 = A070196(121) = 121 + 112 is prime.

%e a(5) = 277 is a term in three ways: 277 = 143 + 134 = 152 + 125 = 161 + 116.

%p f:= proc(n) local L,i;

%p L:= sort(convert(n,base,10),`>`);

%p add(L[i]*10^(i-1),i=1..nops(L)) + n;

%p end proc:

%p select(t -> t < 10000 and isprime(t), map(f, {$1..9999}));

%o (Python)

%o from sympy import isprime

%o def aupto(LIMIT):

%o cands = set(k + int("".join(sorted(str(k)))) for k in range(LIMIT))

%o return sorted(k for k in cands if k <= LIMIT and isprime(k))

%o print(aupto(1200)) # _Michael S. Branicky_, Jan 15 2024

%Y Cf. A070196.

%K nonn,base

%O 1,1

%A _Robert Israel_, Jan 15 2024