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A087062 Array T(n,k) = dismal product n*k (n >= 1, k >= 1) read by antidiagonals. 18
1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 3, 2, 1, 1, 2, 3, 3, 2, 1, 1, 2, 3, 4, 3, 2, 1, 1, 2, 3, 4, 4, 3, 2, 1, 1, 2, 3, 4, 5, 4, 3, 2, 1, 10, 2, 3, 4, 5, 5, 4, 3, 2, 10, 11, 10, 3, 4, 5, 6, 5, 4, 3, 10, 11, 11, 11, 10, 4, 5, 6, 6, 5, 4, 10, 11, 11, 11, 12, 11, 10, 5, 6, 7, 6, 5, 10, 11, 12, 11, 11, 12, 12 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,5

COMMENTS

See A087061 for definition. Note that 0+x = x and 9*x = x for all x.

This differs from A003983 at a(46): min(1,10)=1, while dismal product 10*1 = 10.

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..10011

D. Applegate, C program for dismal arithmetic and number theory

D. Applegate, M. LeBrun and N. J. A. Sloane, Dismal Arithmetic

Index entries for sequences related to dismal arithmetic

EXAMPLE

Dismal multiplication table begins:

1 1 1 1 1 ...

1 2 2 2 2 ...

1 2 3 3 3 ...

1 2 3 4 4 ...

1 2 3 4 5 ...

MAPLE

# convert decimal to string: rec := proc(n) local t0, t1, e, l; if n <= 0 then RETURN([[0], 1]); fi; t0 := n mod 10; t1 := (n-t0)/10; e := [t0]; l := 1; while t1 <> 0 do t0 := t1 mod 10; t1 := (t1-t0)/10; l := l+1; e := [op(e), t0]; od; RETURN([e, l]); end;

# convert string to decimal: cer := proc(ep) local i, e, l, t1; e := ep[1]; l := ep[2]; t1 := 0; if l <= 0 then RETURN(t1); fi; for i from 1 to l do t1 := t1+10^(i-1)*e[i]; od; RETURN(t1); end;

# dismal addition: dadd := proc(m, n) local i, r1, r2, e1, e2, l1, l2, l, l3, t0; r1 := rec(m); r2 := rec(n); e1 := r1[1]; e2 := r2[1]; l1 := r1[2]; l2 := r2[2]; l := max(l1, l2); l3 := min(l1, l2); t0 := array(1..l); for i from 1 to l3 do t0[i] := max(e1[i], e2[i]); od; if l>l3 then for i from l3+1 to l do if l1>l2 then t0[i] := e1[i]; else t0[i] := e2[i]; fi; od; fi; cer([t0, l]); end;

# dismal multiplication: dmul := proc(m, n) local k, i, j, r1, r2, e1, e2, l1, l2, l, t0; r1 := rec(m); r2 := rec(n); e1 := r1[1]; e2 := r2[1]; l1 := r1[2]; l2 := r2[2]; l := l1+l2-1; t0 := array(1..l); for i from 1 to l do t0[i] := 0; od; for i from 1 to l2 do for j from 1 to l1 do k := min(e2[i], e1[j]); t0[i+j-1] := max(t0[i+j-1], k); od; od; cer([t0, l]); end;

CROSSREFS

Cf. A087061 (addition).

Sequence in context: A054526 A113453 A003983 * A204026 A110537 A144434

Adjacent sequences:  A087059 A087060 A087061 * A087063 A087064 A087065

KEYWORD

nonn,tabl,nice,base

AUTHOR

Marc LeBrun (mlb(AT)well.com), Oct 09 2003

EXTENSIONS

Maple programs from N. J. A. Sloane (njas(AT)research.att.com).

Incorrect comment and Mathematica program removed by David Applegate (david(AT)research.att.com), Jan 03 2012

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.