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A092890
Fourth component of quadruples a,b,c,d such that a < b < c < d, (a*b*c) mod (a+b+c) = d, (a*b*d) mod (a+b+d) = c, (a*c*d) mod (a+c+d) = b, (b*c*d) mod (b+c+d) = a. The quadruples are ordered according to sum of first three components, secondary by first component, thirdly by second component.
4
76, 124, 160, 171, 160, 196, 196, 227, 294, 300, 270, 358, 231, 391, 430, 430, 352, 340, 368, 402, 474, 632, 459, 398, 446, 600, 646, 497, 587, 574, 524, 706, 551, 728, 793, 567, 702, 770, 916, 895, 875, 600, 940, 910, 750, 767, 1030, 842, 1020, 1010, 893, 986
OFFSET
1,1
COMMENTS
Suggested by Thomas A. Nagy. - A092887 gives first component, A092888 gives second component, A092889 gives third component.
EXAMPLE
The third quadruple is 12, 60, 128, 160, hence a(3) = 160.
PROG
(PARI) {m=1105; for(n=6, m, for(a=1, (n-3)\3, for(b=a+1, (n-a-1)\2, c=n-a-b; d=a*b*c%(a+b+c); if(c<d, if(a*b*d%(a+b+d)==c, if(a*c*d%(a+c+d)==b, if(b*c*d%(b+c+d)==a, print1(d, ", "))))))))}
CROSSREFS
KEYWORD
nonn
AUTHOR
Klaus Brockhaus, Mar 12 2004
STATUS
approved