A082805 Duplicate of A071119.
2, 3, 5, 7, 131, 151, 353, 373, 727, 757, 929, 11311, 31513, 33533, 37273, 37573
Offset: 1
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.
a(12)=10301 is palindromic prime and its middle digit 3 is prime, a(13)=10501 is palindromic prime and its middle digit 5 is prime, a(14)=11311 is palindromic prime and its middle digit 3 is prime, ...
ts_numprapal := proc(n) local ad,adr,midigit; ad := convert(n,base,10): adr := ListTools[Reverse](ad): if nops(ad) mod 2 = 0 then return 1; fi; midigit := op( (nops(ad)+1)/2,ad ): if (isprime( midigit )='true' and adr=ad) then return 0; else return 1; fi end: ts_pra_num_pal := proc(n) local p1; p1 := ithprime(n): if ts_numprapal(p1) = 0 then return (p1) fi end: apranumpal := [seq(ts_pra_num_pal(i), i=1..100000)]: apranumpal;
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