[go: up one dir, main page]

login
Search: a101254 -id:a101254
     Sort: relevance | references | number | modified | created      Format: long | short | data
a(n) = A101254(n) + A098661(n).
+20
0
4, 52, 232, 1028, 3846, 16678, 89584, 409894, 2166630, 12433014, 67381452, 468282278, 2914549798, 23237125624, 148957518364
OFFSET
1,1
KEYWORD
nonn
AUTHOR
Jonathan Vos Post, Dec 25 2004
EXTENSIONS
Edited and extended by David Wasserman, Mar 27 2008
STATUS
approved
a(n) = sum[i=1,n](i-th prime of Erdős-Selfridge classification i+). Cumulative sums of A101253.
+10
1
2, 21, 134, 751, 2628, 11381, 63898, 318941, 1851114, 11138635, 59638094, 413291157, 2550007678, 20721795665, 132517178106
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.
EXAMPLE
a(11) = 59638094 = 2 * 29 * 1028243 = 2+19+113+617+1877+8753+52517+255043+1532173+9287521+48499459
CROSSREFS
KEYWORD
nonn
AUTHOR
Jonathan Vos Post, Dec 19 2004
EXTENSIONS
More terms from David Wasserman, Mar 26 2008
STATUS
approved

Search completed in 0.012 seconds