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A098661 a(n) = sum[i=1,n](i-th prime of Erdős-Selfridge classification i+). Cumulative sums of A101253. 1
2, 21, 134, 751, 2628, 11381, 63898, 318941, 1851114, 11138635, 59638094, 413291157, 2550007678, 20721795665, 132517178106 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The cumulative sums of the diagonalization of the set of sequences {j-th prime of Erdős-Selfridge classification k+}. The diagonalization itself is in A101253. a(1) = 2 and a(4) = 751 are primes. a(2) = 21 = 3 * 7, a(3) = 134 = 2 * 67; and a(6) = 11381 = 19 * 599 are semiprime. There are only 2 distinct digits in the greatest factor of a(10) = 11138635 = 5 * 2227727. The cumulative sums of the diagonalization of the related set of sequences {j-th prime of Erdős-Selfridge classification k-} is A101254. That n- diagonalization itself is in A101231.
LINKS
EXAMPLE
a(11) = 59638094 = 2 * 29 * 1028243 = 2+19+113+617+1877+8753+52517+255043+1532173+9287521+48499459
CROSSREFS
Sequence in context: A109789 A136588 A171009 * A095262 A209519 A215710
KEYWORD
nonn
AUTHOR
Jonathan Vos Post, Dec 19 2004
EXTENSIONS
More terms from David Wasserman, Mar 26 2008
STATUS
approved

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Last modified March 18 22:27 EDT 2024. Contains 370951 sequences. (Running on oeis4.)