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.
61 is in the sequence because 16 = 4^2. 163 is in the sequence because 361 = 19^2. 167 is not in the sequence because 761 is also prime, not a square.
[p: p in PrimesUpTo(150000)|IsSquare(Seqint(Reverse(Intseq(p))))];// Marius A. Burtea, Jan 12 2019
revdigs:= proc(n)
local L,nL,j;
L:= convert(n,base,10);
nL:= nops(L);
add(L[i]*10^(nL-i),i=1..nL);
end:
map(proc(i) local r; r:= revdigs(i^2); if isprime(r) then r else NULL fi end proc, {$1..9999}); # Robert Israel, Aug 14 2014
Select[Prime[Range[16000]], IntegerQ[Sqrt[ToExpression[StringReverse[ToString[#]]]]] &] Select[Prime[Range[16000]], IntegerQ[Sqrt[FromDigits[ Reverse[ IntegerDigits[ #]]]]] &] (* Harvey P. Dale, Jul 19 2011 *) Select[Prime@ Range[10^5], IntegerQ@ Sqrt@ IntegerReverse@ # &] (* Michael De Vlieger, Jan 20 2018 *)
is(n)=isprime(n) && issquare(fromdigits(Vecrev(digits(n)))) \\ Charles R Greathouse IV, Feb 06 2017
uptoQdigits(n) = {my(res=List(), i2); for(i=4, sqrtint(10^n), i2 = i^2; if(i%10!=0 && gcd(10, i2 \ (10^logint(i2, 10))) == 1, c=fromdigits(Vecrev(digits(i2))); if(isprime(c), listput(res,c) ) ) ); listsort(res); res } \\ David A. Corneth, Jan 12 2019
from gmpy2 import is_square from sympy import prime A007488 = [prime(n) for n in range(1,10**6) if is_square(int(str(prime(n))[::-1]))] # Chai Wah Wu, Aug 14 2014
Union[(i=IntegerReverse)@Select[Range@1000^9,PrimeQ@i@#&]] (* Giorgos Kalogeropoulos, Jan 04 2022 *) Select[IntegerReverse/@(Range[1000]^9),PrimeQ]//Union (* Harvey P. Dale, Nov 27 2024 *)
flip(n)=fromdigits(Vecrev(digits(n))) \\ A004086 Set(select(isprime, vector(1000, n, flip(n^9)))) \\ adapted from A057699
from sympy import isprime flip9 = (int(str(k**9)[::-1]) for k in range(1, 1000) if k%10) print(sorted(filter(isprime, flip9))) # Michael S. Branicky, Jan 02 2022
1815848 is a term because it is a cube and 8485181 is a prime.
rev := proc (n) local nn: nn := convert(n, base, 10): add(nn[j]*10^(nops(nn)-j), j = 1 .. nops(nn)) end proc: a := proc (n) if isprime(rev(n^3)) = true then n^3 else end if end proc: seq(a(n), n = 1 .. 460); # Emeric Deutsch, Jun 27 2009
Select[Range[500]^3,PrimeQ[IntegerReverse[#]]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 03 2019 *)
lista(nn) = { for(n=1, nn, if(ispseudoprime(eval(concat(Vecrev(Str(n^3))))), print1(n^3, ", ")); ); } \\ Altug Alkan, Dec 20 2015
from sympy import isprime A161354_list, i, j = [], 0, 0 while j < 10**15: p = int(str(j)[::-1]) if isprime(p): A161354_list.append(j) j += 3*i*(i+1)+1 i += 1 A161354_list = sorted(A161354_list) # Chai Wah Wu, Dec 20 2015
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