|
%I #17 Jun 23 2023 15:55:06
%S 2,13,0,15913,38131823,0,55626976839097,715233139475563,0,
%T 2939495969798999109119,1324354657687990101112123,0,
%U 4760738699112125138151164177190203,617589103117131145159173187201215229243,0,2339557187103119135151167183199215231247263
%N 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.
%C a(211) has 1008 digits. - _Michael S. Branicky_, Jun 23 2023
%H Michael S. Branicky, <a href="/A088253/b088253.txt">Table of n, a(n) for n = 1..210</a>
%F a(3*k) = 0. - _Michael S. Branicky_, Jun 23 2023
%e The terms of the A.P. in triangular form
%e 2
%e 1 3
%e 0 0 0
%e 1 5 9 13
%e 3 8 13 18 23
%e 0 0 0 0 0 0
%e ...
%e Sequence contains the primes arising as a concatenation of the terms of the n-th row.
%o (Python)
%o from gmpy2 import is_prime
%o from itertools import count
%o 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
%o print([a(n) for n in range(1, 19)]) # _Michael S. Branicky_, Jun 23 2023
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, Sep 26 2003
%E a(7)-a(10) from _Charlie Neder_, May 12 2019
%E a(11) and beyond from _Michael S. Branicky_, Jun 23 2023
| 