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A232171 a(n) = the smallest squarefree number (A005117) with n prime factors in a prime(m) + m progression. 2
2, 6, 30, 61813313, 206658174154973 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Let p(m) = prime(m), let i(p(m)) = m, the subscript of p(m); a(n) = the smallest squarefree number with n prime factors of the form p_1 * p_2 * p_3 * ... * p_n, where p_1 < p_2 < p_3 < ... < p_n with p_n = p_(n-1) + i(p_(n-1)).
a(6) > 10^28.
LINKS
EXAMPLE
206658174154973 = 521*619*733*863*1013; 619 = 521 + 98, 733 = 619 + 114, 863 = 733 + 130, 1013 = 863 + 150 (521 = 98th prime, 619 = 114th prime, 733 = 130th prime, 863 = 150th prime).
CROSSREFS
Sequence in context: A352127 A153046 A088260 * A231816 A058028 A216834
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Nov 19 2013
STATUS
approved

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Last modified March 29 09:14 EDT 2024. Contains 371268 sequences. (Running on oeis4.)