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A104366
Smallest prime factor of A104365(n) = A104350(n) + 1.
8
2, 3, 7, 13, 61, 181, 13, 2521, 7561, 103, 415801, 1247401, 167, 191, 211, 127, 23, 40357, 1099944846001, 349, 41, 251, 37, 2243, 146100174169950001, 103, 53, 1217, 1156675078903494150001, 47, 2939, 251, 857, 41, 547, 13127, 47, 48563, 281, 1336484560722851, 479, 373, 2179, 577670972464621571, 17491, 1399, 97, 22893547
OFFSET
1,1
COMMENTS
a(n) = A020639(A104365(n)).
LINKS
Tyler Busby, Table of n, a(n) for n = 1..170 (terms 1..100 from Chai Wah Wu, terms 101..165 from Max Alekseyev)
PROG
(PARI) gpf(n) = if (n==1, 1, vecmax(factor(n)[, 1])); \\ A006530
spf(n) = if (n==1, 1, vecmin(factor(n)[, 1])); \\ A020639
a(n) = spf(prod(i=2, n, gpf(i))+1); \\ Michel Marcus, Feb 21 2023
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Mar 06 2005
EXTENSIONS
Corrected by D. S. McNeil, Dec 10 2010
STATUS
approved