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%I #24 Mar 13 2021 12:19:28
%S 3,11,19,193,1061,1934071
%N Product of prime and previous prime is palindromic.
%C No further terms < 4.5*10^8.
%C No further terms < 3.7*10^10. - _Michael S. Branicky_, Mar 11 2021
%C No further terms < 5.7*10^11. - _Jon E. Schoenfield_, Mar 13 2021
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/sequenc.htm">More palindromic products of integer sequences</a>
%e 19 belongs to this sequence as 17*19 = 323.
%t p=2; t={}; Do[q=NextPrime[p]; If[Reverse[x=IntegerDigits[p*q]]==x,AppendTo[t,q]]; p=q,{n,150000}]; t (* _Jayanta Basu_, Jun 05 2013 *)
%t Select[Partition[Prime[Range[150000]],2,1],PalindromeQ[Times@@#]&] [[All,2]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Oct 26 2020 *)
%o (Python)
%o from sympy import nextprime
%o def ispal(n): s = str(n); return s == s[::-1]
%o def aupto(lim):
%o prevp, p, alst = 2, 3, []
%o while p < lim:
%o if ispal(p * prevp): alst.append(p)
%o prevp, p = p, nextprime(p)
%o return alst
%o print(aupto(2*10**6)) # _Michael S. Branicky_, Mar 11 2021
%Y Cf. A028979, A028888.
%Y Intersection of A006094 and A002113.
%K nonn,base,more
%O 1,1
%A _Patrick De Geest_
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