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.

A160337 1 plus primes using only digits {0, 1, 2, 3, 5, 7}.

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%I A160337 #20 Jan 25 2021 19:28:49
%S A160337 1,2,3,5,7,11,13,17,23,31,37,53,71,73,101,103,107,113,127,131,137,151,
%T A160337 157,173,211,223,227,233,251,257,271,277,307,311,313,317,331,337,353,
%U A160337 373,503,521,523,557,571,577,701,727,733,751,757,773,1013,1021,1031
%N A160337 1 plus primes using only digits {0, 1, 2, 3, 5, 7}.
%H A160337 Alois P. Heinz, <a href="/A160337/b160337.txt">Table of n, a(n) for n = 1..10000</a>
%o A160337 (C++)
%o A160337 #include <iostream>
%o A160337 using namespace std;
%o A160337 bool isPrime(long n)
%o A160337 {
%o A160337     if(n==0) return true;
%o A160337     for(long i = 2; i<=n/2; i++) { if(n%i == 0) return false; }
%o A160337     return true;
%o A160337 }
%o A160337 bool checkdigit(long n)
%o A160337 {
%o A160337     long no = n;
%o A160337     while(no>0)
%o A160337     {
%o A160337         long digit = no%10;
%o A160337         if(digit==0) return false;
%o A160337         else { if(!isPrime (digit)) return false; }
%o A160337         no = no/10;
%o A160337     }
%o A160337     return true;
%o A160337 }
%o A160337 int main()
%o A160337 {
%o A160337     long limit = 1000000000; int count =0;
%o A160337     for(long i=1; i<=limit; i++)
%o A160337     {
%o A160337         if(isPrime(i) && checkdigit(i))
%o A160337         { count++; cout<<i<<endl; }
%o A160337         if(count == 100) { return 0; }
%o A160337     }
%o A160337     return 0;
%o A160337 }
%o A160337 (Python)
%o A160337 from sympy import isprime
%o A160337 def ok(n): return n == 1 or (set(str(n)) <= set("012357") and isprime(n))
%o A160337 print([m for m in range(1032) if ok(m)]) # _Michael S. Branicky_, Jan 25 2021
%Y A160337 Cf. A012884, A143390.
%K A160337 nonn,base
%O A160337 1,2
%A A160337 Mohit Singh Kanwal (mohit_kanwal(AT)hotmail.com), May 10 2009