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 A175411 a(n) = Sum_{i=(n*n-n+2)/2..(n*n+n)/2} i!. 0
 1, 8, 864, 4037040, 1401598598400, 53652268264218624000, 316196664157721349185863680000, 382630662500715988102392981826830336000000, 122342346998826334909002798912467017444232685158400000000, 12931604174610554670466196146308122246477496321113350463375278080000000000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Table of n, a(n) for n=1..10. EXAMPLE a(4) = 7! + 8! + 9! + 10! = 4037074. PROG (PARI) a(n)= sum(i=(n^2-n+2)/2, (n^2+n)/2, i!); \\ Michel Marcus, Mar 15 2022 CROSSREFS Cf. A000142. Sequence in context: A097818 A360195 A262379 * A027725 A265239 A290023 Adjacent sequences: A175408 A175409 A175410 * A175412 A175413 A175414 KEYWORD easy,nonn AUTHOR Ctibor O. Zizka, May 07 2010 EXTENSIONS a(4) corrected and more terms from Michel Marcus, Mar 15 2022 STATUS approved

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Last modified August 11 17:02 EDT 2024. Contains 375073 sequences. (Running on oeis4.)