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 A109061 To compute a(n) we first write down 9^n 1's in a row. Each row takes the rightmost 9th 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 9th part. The single element in the last row is a(n). 6
 1, 1, 9, 693, 476121, 2940705927, 163444130390781 (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.....70..71..72..73..74..75..76..77..78..79..80..81 ........................73.147.222.298.375.453.532.612.693 .......................................................693 Therefore a(3)=693. 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=8*nops(L)/9+1..j), j=8*nops(L)/9+1..nops(L))]; a:=f([seq(1, j=1..9^n)]); while nops(a)>9 do a:=f(a) end do; a[9]; end proc; CROSSREFS Cf. A107354, A109055, A109056, A109057, A109058, A109059, A109060, A109062. Sequence in context: A053973 A059492 A322488 * A282181 A053515 A120816 Adjacent sequences:  A109058 A109059 A109060 * A109062 A109063 A109064 KEYWORD nonn AUTHOR Augustine O. Munagi, Jun 17 2005 STATUS approved

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Last modified October 18 23:39 EDT 2019. Contains 328211 sequences. (Running on oeis4.)