A024783 Every suffix prime and no 0 digits in base 8 (written in base 8).

2, 3, 5, 7, 13, 15, 23, 27, 35, 37, 45, 53, 57, 65, 73, 75, 123, 145, 153, 213, 227, 235, 265, 323, 337, 345, 357, 373, 415, 445, 475, 513, 535, 557, 565, 573, 615, 645, 657, 673, 715, 723, 737, 753, 775, 1145, 1153, 1357, 1475, 1737, 1775, 2213, 2235, 2535, 3123, 3145

Offset

1,1

Comments

The final term of the sequence is a(446) = 313636165537775.

Links

Nathaniel Johnston, Table of n, a(n) for n = 1..446 (full sequence)

Maple

a:=[[2], [3], [5], [7]]: l1:=1: l2:=4: do for k from 1 to 7 do for j from l1 to l2 do d:=[op(a[j]), k]: if(isprime(op(convert(d, base, 8, 8^nops(d)))))then a:=[op(a), d]: fi: od: od: l1:=l2+1: l2:=nops(a): if(l1>l2)then break: fi: od: seq(op(convert(a[j], base, 10, 10^nops(a[j]))), j=1..nops(a)); # Nathaniel Johnston, Jun 21 2011

Prog

(Python)
from sympy import isprime
def afull():
    prime_strings, alst = list("2357"), []
    while len(prime_strings) > 0:
        alst.extend(sorted(int(p) for p in prime_strings))
        candidates = set(d+p for p in prime_strings for d in "1234567")
        prime_strings = [c for c in candidates if isprime(int(c, 8))]
    return alst
print(afull()) # Michael S. Branicky, Apr 27 2022

Crossrefs

Cf. A024779, A024780, A024781, A024782, A024784, A024785.

Sequence in context: A031344 A004682 A173105 * A092855 A100111 A092878

Adjacent sequences: A024780 A024781 A024782 * A024784 A024785 A024786

Keyword

nonn,base,easy,fini,full

Author

David W. Wilson

Status

approved