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A359697
Triangle T(n,k), n >= 1, 1 <= k <= n, read by rows, where T(n,k) is carryless product n X k base 10.
2
1, 2, 4, 3, 6, 9, 4, 8, 2, 6, 5, 0, 5, 0, 5, 6, 2, 8, 4, 0, 6, 7, 4, 1, 8, 5, 2, 9, 8, 6, 4, 2, 0, 8, 6, 4, 9, 8, 7, 6, 5, 4, 3, 2, 1, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 11, 22, 33, 44, 55, 66, 77, 88, 99, 110, 121, 12, 24, 36, 48, 50, 62, 74, 86, 98, 120, 132, 144
OFFSET
1,2
EXAMPLE
Triangle begins:
1;
2, 4;
3, 6, 9;
4, 8, 2, 6;
5, 0, 5, 0, 5;
6, 2, 8, 4, 0, 6;
7, 4, 1, 8, 5, 2, 9;
8, 6, 4, 2, 0, 8, 6, 4;
9, 8, 7, 6, 5, 4, 3, 2, 1;
10, 20, 30, 40, 50, 60, 70, 80, 90, 100;
11, 22, 33, 44, 55, 66, 77, 88, 99, 110, 121;
12, 24, 36, 48, 50, 62, 74, 86, 98, 120, 132, 144;
PROG
(PARI) T(n, k) = fromdigits(Vec(Pol(digits(n))*Pol(digits(k)))%10);
CROSSREFS
T(n,n) gives A059729.
Cf. A001477 for carryless 1 X n, A004520 for carryless 2 X n base 10, A055120 for carryless 9 X n, A008592 for carryless 10 X n, A059691 for carryless 12 X n.
Sequence in context: A077661 A077583 A153125 * A139413 A075362 A110749
KEYWORD
nonn,tabl,base,look
AUTHOR
Seiichi Manyama, Mar 08 2023
STATUS
approved