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A075246 y-value of the solution (x,y,z) to 4/n = 1/x + 1/y + 1/z satisfying 0 < x < y < z and having the largest z-value. The x and z components are in A075245 and A075247. 14
4, 3, 4, 7, 15, 7, 10, 16, 34, 13, 18, 29, 61, 21, 30, 46, 96, 31, 43, 67, 139, 43, 60, 92, 190, 57, 78, 121, 249, 73, 100, 154, 316, 91, 124, 191, 391, 111, 154, 232, 474, 133, 181, 277, 565, 157, 99, 326, 664, 183, 248, 379, 771, 211, 286, 436, 886, 241, 326 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,1

COMMENTS

See A073101 for more details.

LINKS

Table of n, a(n) for n=3..61.

MAPLE

A075246:=proc() local t, n, a, b, t1, largey, largez; for n from 3 to 100 do t:=4/n; largez:=0; largey:=0; for a from floor(1/t)+1 to floor(3/t) do t1:=t - 1/a; for b from max(a, floor(1/t1)+1) to floor(2/(t1)) do if and(type(1/(t1 - 1/b), integer), a<b, b<(1/(t1 - 1/b))) then if (1/(t1 - 1/b))>largez then largez:=(1/(t1 - 1/b)); largey:=b; end if end if end do; end do; lprint(n, largey) end do; end proc; # [program derived from A192787] Patrick J. McNab, Aug 20 2014

MATHEMATICA

For[xLst={}; yLst={}; zLst={}; n=3, n<=100, n++, cnt=0; xr=n/4; If[IntegerQ[xr], x=xr+1, x=Ceiling[xr]]; While[yr=1/(4/n-1/x); If[IntegerQ[yr], y=yr+1, y=Ceiling[yr]]; cnt==0&&y>x, While[zr=1/(4/n-1/x-1/y); cnt==0&&zr>y, If[IntegerQ[zr], z=zr; cnt++; AppendTo[xLst, x]; AppendTo[yLst, y]; AppendTo[zLst, z]]; y++ ]; x++ ]]; yLst

CROSSREFS

Cf. A073101, A075245, A075247, A192787.

Sequence in context: A200592 A021027 A289672 * A257840 A132984 A277528

Adjacent sequences:  A075243 A075244 A075245 * A075247 A075248 A075249

KEYWORD

hard,nice,nonn

AUTHOR

T. D. Noe, Sep 10 2002

STATUS

approved

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Last modified May 23 01:37 EDT 2019. Contains 323507 sequences. (Running on oeis4.)