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A096358
Integer part of the third nesting of the logarithmic integral of 10^n.
0
3, 7, 17, 52, 207, 999, 5537, 33753, 220283, 1513863, 10833986, 80107339, 608461893, 4726899406, 37431060563, 301327400284, 2460711991071, 20348626872625, 170149288404678, 1436870810843313
OFFSET
1,1
FORMULA
Let Li(n) = logarithmic integral of n. a(n) = Li(Li(Li(n)))
PROG
(PARI) \p 100 f(n) = for(x=1, n, print1(floor(Li(Li(Li(10^x))))", ")) Li(x) = { -eint1(log(1/x)) }
CROSSREFS
Sequence in context: A014144 A247183 A321139 * A359174 A260349 A146147
KEYWORD
nonn
AUTHOR
Cino Hilliard, Jun 30 2004
STATUS
approved