OFFSET
1,1
COMMENTS
This sequence contains straight-line primes (A167847).
a(216) has 1012 digits. - Michael S. Branicky, Aug 05 2022
LINKS
Michael S. Branicky, Table of n, a(n) for n = 1..215 (terms 1..147 from Paul Tek)
Paul Tek, PARI program for this sequence
EXAMPLE
(7,2,7,2,7,...) is an arithmetic progression mod 10, hence the prime number 72727 appears in this sequence.
(7,6,5,4,3,...) is an arithmetic progression mod 10, hence the prime number 76543 appears in this sequence.
MATHEMATICA
Select[Prime[Range[PrimePi[76543]]], Length[Union[Mod[Differences[IntegerDigits[#]], 10]]] <= 1 &]
PROG
(PARI) See Link section.
(Python)
from sympy import isprime
from itertools import count, islice
def bgen():
yield from [2, 3, 5, 7]
yield from (int("".join(str((s0+i*r)%10) for i in range(d))) for d in count(2) for s0 in range(1, 10) for r in range(-s0, 10-s0))
def agen(): yield from filter(isprime, bgen())
print(list(islice(agen(), 52))) # Michael S. Branicky, Aug 05 2022
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Paul Tek, Nov 11 2013
STATUS
approved