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%I #14 Jul 11 2022 19:58:25
%S 11,13,17,19,37,41,53,59,61,67,71,79,89,97,107,109,113,131,151,167,
%T 179,193,199,211,257,277,293,313,337,359,373,383,389,409,457,479,577,
%U 599,613,617,659,661,673,691,701,709,727,739,751,757,827,829,839,863,883
%N Primes that remain prime when a 0 is inserted between every pair of adjacent digits.
%C Prime terms in A050674.
%C See A119680 for the primes obtained by inserting a 0 between each pair of adjacent digits. - _Rémy Sigrist_, Oct 08 2017
%H Harvey P. Dale, <a href="/A159236/b159236.txt">Table of n, a(n) for n = 1..1000</a>
%e 409 is prime, and so is 40009 ( 4(0)0(0)9 ). Hence 409 is in the sequence.
%p Lton := proc(L) add( op(i,L)*10^(i-1),i=1..nops(L)) ; end: pad0 := proc(n) dgs := convert(n,base,10) ; L := [op(1,dgs)] ; for i from 2 to nops(dgs) do L := [op(L),0,op(i,dgs)] ; od: Lton(L) ; end: for i from 5 to 400 do p := ithprime(i) ; if isprime( pad0(p) ) then printf("%d,",p) ; fi; od: # _R. J. Mathar_, Apr 07 2009
%t Select[Prime[Range[5,200]],PrimeQ[FromDigits[Riffle[ IntegerDigits[ #],0]]]&] (* _Harvey P. Dale_, Feb 19 2015 *)
%o (Python)
%o from sympy import isprime
%o def ok(n):
%o return n > 10 and isprime(n) and isprime(int("0".join(list(str(n)))))
%o print([k for k in range(900) if ok(k)]) # _Michael S. Branicky_, Jul 11 2022
%Y Cf. A050674, A119680.
%K nonn,base
%O 1,1
%A _Lekraj Beedassy_, Apr 06 2009
%E Edited by _N. J. A. Sloane_, Apr 07 2009
%E Extended by _R. J. Mathar_, Apr 07 2009
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