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.
s = 0; Do[k = 0; While[k < 2^n, k++; If[p = FromDigits[ PadLeft[ IntegerDigits[k, 2], n] + 2]; PrimeQ[p], s++ ]]; Print[s], {n, 1, 22}]
With[{c=Select[Flatten[Table[FromDigits/@Tuples[{2,3},n],{n,22}]], PrimeQ]}, Table[Count[c,?(#<10^i&)],{i,22}]] (* _Harvey P. Dale, Mar 18 2016 *)
from sympy import isprime
from itertools import count, islice, product
def agen(): # generator of terms
c = 2
for d in count(2):
yield c
for first in product("23", repeat=d-1):
t = int("".join(first) + "3")
if isprime(t): c += 1
print(list(islice(agen(), 20))) # Michael S. Branicky, May 23 2024
a = {}; Do[If[PrimeQ[(n! + 8)/8], AppendTo[a, (n! + 8)/8]], {n, 1, 50}]; a
Select[(8+Range[50]!)/8,PrimeQ] (* Harvey P. Dale, May 10 2016 *)
for(k=4,1e3,if(ispseudoprime(t=k!/8+1),print1(t", "))) \\ Charles R Greathouse IV, Jul 15 2011
a = {}; Do[If[PrimeQ[(n! + 9)/9], AppendTo[a, (n! + 9)/9]], {n, 1, 150}]; a
Select[Range[100]!/9+1,PrimeQ] (* Harvey P. Dale, Aug 17 2017 *)
for(n=6,1e4,if(ispseudoprime(t=n!/9+1),print1(t", "))) \\ Charles R Greathouse IV, Jul 15 2011
a = {}; Do[If[PrimeQ[(n! + 10)/10], AppendTo[a, (n! + 10)/10]], {n, 1, 50}]; a
Select[(Range[50]!+10)/10,PrimeQ] (* Harvey P. Dale, Sep 18 2013 *)
for(k=5,1e3,if(ispseudoprime(t=k!/10+1),print1(t", "))) \\ Charles R Greathouse IV, Jul 15 2011
a = {}; Do[k = 1; While[ ! PrimeQ[(Prime[k]! + n)/n], k++ ]; AppendTo[a, Prime[(Prime[k]! + n)/n]], {n, 1, 8}]; a
a032810 = f 0 . (+ 1) where f y 1 = a004086 y f y x = f (10 * y + m + 2) x' where (x', m) = divMod x 2 -- Reinhard Zumkeller, Mar 18 2015
[n: n in [1..24000] | Set(Intseq(n)) subset {2, 3}]; // Vincenzo Librandi, May 27 2012
[n eq 1 select 2 else IsOdd(n) select 10*Self(Floor(n/2))+2 else Self(n-1)+1: n in [1..40]]; // Bruno Berselli, May 27 2012
Flatten[Table[FromDigits[#,10]&/@Tuples[{2,3},n],{n,5}]] (* Vincenzo Librandi, May 27 2012 *)
A032810(n)=vector(#n=binary(n+1)[2..-1],i,10^(#n-i))*n~+10^#n\9*2 \\ M. F. Hasler, Mar 26 2015
def A032810(n): return int(bin(n+1)[3:])+(10**((n+1).bit_length()-1)-1<<1)//9 # Chai Wah Wu, Jul 15 2023
a = {}; Do[If[PrimeQ[(n! + 4)/4], AppendTo[a, n]], {n, 1, 500}]; a
Select[Range[500],PrimeQ[(4+#!)/4]&] (* Harvey P. Dale, Mar 24 2011 *)
for(n=4,1e3,if(ispseudoprime(n!/4+1),print1(n", "))) \\ Charles R Greathouse IV, Jul 15 2011
a = {}; Do[If[PrimeQ[(n! + 6)/6], AppendTo[a, n]], {n, 1, 500}]; a
for(k=3,1e3,if(ispseudoprime(k!/6+1),print1(k", "))) \\ Charles R Greathouse IV, Jul 15 2011
a = {}; Do[If[PrimeQ[(n! + 7)/7], AppendTo[a, n]], {n, 1, 500}]; a
Select[Range[500],PrimeQ[(7+#!)/7]&] (* Harvey P. Dale, Sep 01 2014 *)
for(k=7,1e3,if(ispseudoprime(k!/7+1),print1(k", "))) \\ Charles R Greathouse IV, Jul 15 2011
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