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A109057 To compute a(n) we first write down 5^n 1's in a row. Each row takes the rightmost 5th part of the previous row and each element in it equals sum of the elements of the previous row starting with the first of the rightmost 5th part. The single element in the last row is a(n). 8
1, 1, 5, 115, 12885, 7173370, 19940684251, 277078842941900, 19249144351745111125, 6686277384080730564862875, 11612516024884420913314995604000, 100841213012622614260440382077516990500, 4378443591626306255827149380635713364079323075 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
EXAMPLE
For example, for n=3 the array, from 2nd row, follows:
1..2..3.....14..15..16..17..18..19..20..21..22..23..24..25
........................................21..43..66..90.115
.......................................................115
Therefore a(3)=115.
MAPLE
proc(n::nonnegint) local f, a; if n=0 or n=1 then return 1; end if; f:=L->[seq(add(L[i], i=4*nops(L)/5+1..j), j=4*nops(L)/5+1..nops(L))]; a:=f([seq(1, j=1..5^n)]); while nops(a)>5 do a:=f(a) end do; a[5]; end proc;
CROSSREFS
Column k=5 of A355576.
Sequence in context: A208959 A209053 A255884 * A245105 A080988 A230338
KEYWORD
nonn
AUTHOR
Augustine O. Munagi, Jun 17 2005
EXTENSIONS
More terms from Alois P. Heinz, Jul 06 2022
STATUS
approved

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Last modified March 28 16:34 EDT 2024. Contains 371254 sequences. (Running on oeis4.)