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A110353
Value of k pertaining to A110351(n). Least k such that the sum (n+1) + (n+2) + ...+(n+k) is a multiple of the n-th triangular number n(n+1)/2.
3
1, 1, 5, 11, 4, 8, 41, 55, 26, 34, 21, 27, 64, 6, 65, 239, 118, 134, 56, 15, 56, 208, 160, 176, 274, 298, 161, 175, 115, 125, 929, 319, 120, 50, 189, 260, 628, 208, 65, 575, 204, 216, 429, 55, 369, 988, 657, 687, 1126, 324, 221, 584, 1324, 485, 120, 343, 494, 1594
OFFSET
1,3
COMMENTS
For many values of n, a(n) = A110352(n).
LINKS
PROG
(Haskell)
import Data.List (findIndex)
import Data.Maybe (fromJust)
a110353 n = (+ 1) $ fromJust $
findIndex ((== 0) . (`mod` t)) $ dropWhile (<= t) a000217_list
where t = a000217 n
-- Reinhard Zumkeller, Mar 23 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Jul 21 2005
EXTENSIONS
More terms from Joshua Zucker, May 08 2006
STATUS
approved