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A137690 Primes of the form A128646(k)-1 for some k (listed in A137689), where A128646 = denominators of partial sums of 1/(prime(i)-1). 3
3, 11, 59, 79, 719, 7919, 55439, 425039, 5525519, 19709529839, 197095298399, 999294451257532807016639, 2823006824802530179822007999, 2649530397357338361250749788962714016407928543999 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The next term is A128646(243)-1, which has 148 decimal digits. New terms should be added to A137689, not here.
LINKS
PROG
(PARI) A137689_v=[3, 4, 5, 7, 8, 9, 10, 11, 15, 16, 23, 24, 26, 47, 48, 54, 78, 79, 80, 243]/*see there*/;
vecsort(vector(#A137689_v, k, denominator(sum(i=1, A137689_v[k], 1/(prime(i)-1)))/*i.e.
A128646(A137689_v[k])*/-1), 0, 8) /* ..., 8 removes duplicate entries in PARI > 2.4.1 */
CROSSREFS
Sequence in context: A086827 A308487 A164291 * A107007 A199854 A242384
KEYWORD
nonn
AUTHOR
M. F. Hasler, Feb 07 2008
STATUS
approved

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Last modified March 28 18:04 EDT 2024. Contains 371254 sequences. (Running on oeis4.)