login
A220053
Partial sums in rows of A130517, triangle read by rows.
4
1, 2, 3, 3, 4, 6, 4, 6, 7, 10, 5, 8, 9, 11, 15, 6, 10, 12, 13, 16, 21, 7, 12, 15, 16, 18, 22, 28, 8, 14, 18, 20, 21, 24, 29, 36, 9, 16, 21, 24, 25, 27, 31, 37, 45, 10, 18, 24, 28, 30, 31, 34, 39, 46, 55, 11, 20, 27, 32, 35, 36, 38, 42, 48, 56, 66, 12, 22, 30
OFFSET
1,2
LINKS
FORMULA
T(n,k) = Sum_{i=1..k} A130517(n, i).
EXAMPLE
1;
2, 3;
3, 4, 6;
4, 6, 7, 10;
5, 8, 9, 11, 15;
6, 10, 12, 13, 16, 21;
7, 12, 15, 16, 18, 22, 28;
8, 14, 18, 20, 21, 24, 29, 36;
9, 16, 21, 24, 25, 27, 31, 37, 45;
10, 18, 24, 28, 30, 31, 34, 39, 46, 55;
11, 20, 27, 32, 35, 36, 38, 42, 48, 56, 66;
MATHEMATICA
T[n_, 1] := n;
T[n_, n_] := n-1;
T[n_, k_] := Abs[2k - n - If[2k <= n+1, 2, 1]];
row[n_] := Table[T[n, k], {k, 1, n}] // Accumulate;
Table[row[n], {n, 1, 12}] // Flatten (* Jean-François Alcover, Sep 23 2021 *)
PROG
(Haskell)
a220053 n k = a220053_tabl !! (n-1) !! (k-1)
a220053_row n = a220053_tabl !! (n-1)
a220053_tabl = map (scanl1 (+)) a130517_tabl
-- Reinhard Zumkeller, Dec 03 2012
CROSSREFS
Cf. A000027 (left edge), A000217 (right edge), A000290 (central terms), A002717 (row sums); A220075.
Sequence in context: A180986 A200763 A203291 * A320509 A358298 A347712
KEYWORD
nonn,tabl,easy
AUTHOR
Reinhard Zumkeller, Dec 03 2012
STATUS
approved