login

Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.

A088253
Smallest prime whose digits can be partitioned into n successive terms of an A.P. with common difference n, or 0 if no such number exists.
1
2, 13, 0, 15913, 38131823, 0, 55626976839097, 715233139475563, 0, 2939495969798999109119, 1324354657687990101112123, 0, 4760738699112125138151164177190203, 617589103117131145159173187201215229243, 0, 2339557187103119135151167183199215231247263
OFFSET
1,1
COMMENTS
a(211) has 1008 digits. - Michael S. Branicky, Jun 23 2023
LINKS
Michael S. Branicky, Table of n, a(n) for n = 1..210
FORMULA
a(3*k) = 0. - Michael S. Branicky, Jun 23 2023
EXAMPLE
The terms of the A.P. in triangular form
2
1 3
0 0 0
1 5 9 13
3 8 13 18 23
0 0 0 0 0 0
...
Sequence contains the primes arising as a concatenation of the terms of the n-th row.
PROG
(Python)
from gmpy2 import is_prime
from itertools import count
def a(n): return next(t for t in (int("".join(str(i) for i in range(k, k+n*n, n))) for k in count(1)) if is_prime(t)) if n%3 else 0
print([a(n) for n in range(1, 19)]) # Michael S. Branicky, Jun 23 2023
CROSSREFS
Sequence in context: A128033 A090954 A089778 * A249224 A217010 A091023
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Sep 26 2003
EXTENSIONS
a(7)-a(10) from Charlie Neder, May 12 2019
a(11) and beyond from Michael S. Branicky, Jun 23 2023
STATUS
approved