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.
13 is a term since 9012345678901 is a prime.
fQ[n_] := PrimeQ@ FromDigits@ Mod[8+Range@n, 10]; lst = {}; Do[ If[fQ@n, AppendTo[lst, n]; Print@n], {n, 5000}]; lst
Flatten[Position[Table[FromDigits[PadRight[{},n,{9,0,1,2,3,4,5,6,7,8}]],{n,100}],?PrimeQ]] (* _Harvey P. Dale, Sep 06 2015 *)
a(1) = A052015(4), a(2) = A052015(15), a(3) = A052015(35), a(4) = A052015(61), ... In short, a(n) = A052015(b(n)) with b = (4, 15, 35, 61, 81, 94, 98, 100). - _M. F. Hasler_, May 03 2017
A071363(n,u=vectorv(n,i,10^(n-i)))={forvec(d=vector(n,i,[1,9]),isprime(d*u)&&n=d*u,2);n} \\ M. F. Hasler, May 03 2017
fQ[n_]:=Module[{id=IntegerDigits[n],}, n < 10 || Union[Differences[id]] == {-1}]; Select[Prime[Range[10000]], fQ] (* Vladimir Joseph Stephan Orlovsky, Dec 29 2010 *)
def ok(n):
s = str(n)
return s == "".join(str((int(s[0])+i)%10) for i in range(len(s)))
print([k for k in range(10**6) if ok(k)]) # Michael S. Branicky, May 26 2022
from itertools import count, islice
def agen(): # generator of terms
yield 0
for d in count(1):
for s0 in range(1, 10):
yield int("".join(str((s0+i)%10) for i in range(d)))
print(list(islice(agen(), 50))) # Michael S. Branicky, May 26 2022
f[n_] := Block[{d = Reverse@ Range@n, t = Table[1, {n}]}, Select[ Drop[ Union@ Flatten@ Table[ FromDigits[ Mod[d + i*t, 10]], {i, 10}], 2], PrimeQ@# &]]; Array[f, 1000] // Flatten
from sympy import isprime
from itertools import count, islice
def bgen(): yield from (int("".join(str((s0-i)%10) for i in range(d))) for d in count(1) for s0 in range(1, 10))
def agen(): yield from filter(isprime, bgen())
print(list(islice(agen(), 10))) # Michael S. Branicky, Aug 05 2022
f[n_] := Block[{u = Range@n, d = Reverse@ Range@n, t = Table[1, {n}]}, Select[ Drop[ Union@ Flatten@ Table[ FromDigits /@ Mod[{u, d} + {i*t, i*t}, 10], {i, 10}], 2], PrimeQ@# &]]; Array[f, 35] // Flatten
a(9) = 34567 because it is semiprime 13 * 2659, and (3,4,5,6,7) are consecutive ascending digits.
R:= 4, 6, 9: V:= [$1..9]: for d from 2 to 50 do V:= map(n -> 10*n + ((n+1) mod 10), V); W:= select(t -> numtheory:-bigomega(t)=2, V); R:= R, op(W); od: R; # Robert Israel, Nov 15 2023
4321 is in the sequence because it is semiprime 4321 = 29 * 149, and (4,3,2,1) are descending consecutive digits.
Sort[Flatten[Table[Select[FromDigits/@Partition[Range[9,0,-1],n,1], PrimeOmega[#] == 2&],{n,10}]]] (* Harvey P. Dale, Jul 10 2014 *)
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