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A336225 Table read by antidiagonals: T(n, k) = digitsum(n*k) with n >= 0 and k >= 0. 0
0, 0, 0, 0, 1, 0, 0, 2, 2, 0, 0, 3, 4, 3, 0, 0, 4, 6, 6, 4, 0, 0, 5, 8, 9, 8, 5, 0, 0, 6, 1, 3, 3, 1, 6, 0, 0, 7, 3, 6, 7, 6, 3, 7, 0, 0, 8, 5, 9, 2, 2, 9, 5, 8, 0, 0, 9, 7, 3, 6, 7, 6, 3, 7, 9, 0, 0, 1, 9, 6, 10, 3, 3, 10, 6, 9, 1, 0, 0, 2, 2, 9, 5, 8, 9, 8, 5, 9, 2, 2, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,8

LINKS

Table of n, a(n) for n=0..90.

Index entries for sequences related to sum of digits.

FORMULA

T(n, k) = A007953(A004247(n, k)).

T(n, 1) = T(1, n) = A007953(n).

T(n, 2) = T(2, n) = A004092(n).

T(n, k) = A007953(A003991(n, k)) for n*k > 0. - Michel Marcus, Jul 13 2020.

EXAMPLE

The table T(n, k) begins

0   0   0   0   0   0   0   0 ...

0   1   2   3   4   5   6   7 ...

0   2   4   6   8   1   3   5 ...

0   3   6   9   3   6   9   3 ...

0   4   8   3   7   2   6  10 ...

0   5   1   6   2   7   3   8 ...

0   6   3   9   6   3   9   6 ...

0   7   5   3  10   8   6  13 ...

...

MATHEMATICA

T[n_, k_]:=Total[IntegerDigits[n*k]]; Table[T[n-k, k], {n, 0, 12}, {k, 0, n}]//Flatten

PROG

(PARI) T(n, k) = sumdigits(n*k);

CROSSREFS

Cf. A003991, A004092, A004159 (diagonal), A004164 (digitsum of n^3), A004247, A007953, A055565 (digitsum of n^4), A055566 (digitsum of n^5), A055567 (digitsum of n^6).

Sequence in context: A048720 A067138 A059692 * A004247 A271916 A327031

Adjacent sequences:  A336222 A336223 A336224 * A336226 A336227 A336228

KEYWORD

nonn,base,tabl,easy

AUTHOR

Stefano Spezia, Jul 12 2020

STATUS

approved

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Last modified January 22 00:08 EST 2022. Contains 350481 sequences. (Running on oeis4.)