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A181129
Smallest primes of the form (i+1)(i+2)...(h-1)(h)1234...(i-1)(i). These elements, by definition, belong to A001292.
3
2341, 89101234567, 45678910111213123, 23456789101112131415161718192021222324251, 30313233341234567891011121314151617181920212223242526272829, 20212223242526272829303132333435363738394041424344454612345678910111213141516171819, 42434445461234567891011121314151617181920212223242526272829303132333435363738394041, 14151617181920212223242526272829303132333435363738394041424344454647484950515212345678910111213
OFFSET
1,1
COMMENTS
If we indicate by p(j) the j-th term of A001292, the sequence above can be synthesized as:
p(8), p(53), p(82), p(302), p(591), p(1055), p(1077), p(1340), p(1499), p(1890), p(2231), p(3109), p(3145), p(3620), p(3878), p(4405), p(6248), p(8878), p(8888), p(11329), p(11439), p(12310), p(12344), p(13323), p(13747), p(15883), p(17471), p(17985), p(19815), p(20335), p(21676).
The first 30 terms of the sequence contain fewer than 500 digits. Among the first 22155 terms of A001292 only 31 are primes.
REFERENCES
Marco Ripà, "Rudimatematici", Bookshelf, October 2010.
M. Vassilev-Missana and K. Atanassov, "Some Smarandache problems", Hexis, 2004.
LINKS
Michael S. Branicky, Table of n, a(n) for n = 1..46 (terms 1..31 from Marco Ripà)
Kenichiro Kashihara, Comments and Topics on Smarandache Notions and Problems, Erhus University Press, 1996, 50 pages.
Kenichiro Kashihara, Comments and Topics on Smarandache Notions and Problems, Erhus University Press, 1996, 50 pages. [Cached copy]
Marco Ripa, Patterns related to the Smarandache circular sequence primality problem, Notes Numb. Th. Discr. Math., vol. 18(1) (2012), pp. 29-48.
Florentin Smarandache, Only Problems, Not Solutions!, Xiquan Publ., Phoenix-Chicago, 1993.
PROG
(Python) # uses A001292gen() and imports from A001292
from sympy import isprime
def agen(): yield from filter(isprime, A001292gen())
print(list(islice(agen(), 10))) # Michael S. Branicky, Jul 01 2022
CROSSREFS
Sequence in context: A043440 A023938 A132204 * A064868 A263556 A255099
KEYWORD
nonn,base
AUTHOR
Marco Ripà, Jan 23 2011
EXTENSIONS
Edited by N. J. A. Sloane, Jan 25 2011
STATUS
approved