cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A335731 Bemirps that also interpret 2 and 5 as upside-down forms of each other, assuming a digital font.

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%I A335731 #18 Jul 05 2020 12:44:37
%S A335731 1061,1091,1601,1901,10061,10091,16001,19001,106861,109891,110651,
%T A335731 110921,120121,121021,121921,129011,129121,150151,151051,151651,
%U A335731 156011,156151,168601,198901,1022591,1026521,1028011,1055261,1058011,1059251,1069291,1096561,1102891,1105861,1106881,1108201,1108501,1109881,1111651
%N A335731 Bemirps that also interpret 2 and 5 as upside-down forms of each other, assuming a digital font.
%e A335731 110651 is in the list as its upside-down form 110921, and its emirp 156011, and the emirp of its upside-down form 129011, are all primes and uniquely different numbers.
%o A335731 (Python)
%o A335731 from sympy.ntheory import isprime as isp
%o A335731 def ip(pp):
%o A335731     rr = []
%o A335731     for qq in pp:
%o A335731         if qq=="0" or qq=="1" or qq=="8":
%o A335731             rr.append(qq)
%o A335731         elif qq=="2":
%o A335731             rr.append("5")
%o A335731         elif qq=="5":
%o A335731             rr.append("2")
%o A335731         elif qq=="6":
%o A335731             rr.append("9")
%o A335731         elif qq=="9":
%o A335731             rr.append("6")
%o A335731     return "".join(rr)
%o A335731 for bb in range(1,10000000):
%o A335731     if isp(bb):
%o A335731         bb = str(bb)
%o A335731         if ("7" not in bb) and ("4" not in bb) and ("3" not in bb):
%o A335731             cc = bb[::-1]
%o A335731             dd = ip(bb)
%o A335731             ee = ip(cc)
%o A335731             if bb!=cc and dd!=ee and bb!=dd and bb!=ee and cc!=dd and cc!=ee and isp(int(cc)) and isp(int(dd)) and isp(int(ee)):
%o A335731                 print(bb)
%Y A335731 Normal bemirps are defined in A048895.
%K A335731 base,nonn
%O A335731 1,1
%A A335731 _Ray G. Opao_, Jun 20 2020