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A069753
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Smallest k>n such that the tetrahedral number n*(n+1)*(n+2)/6 divides the tetrahedral number k*(k+1)*(k+2)/6.
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0
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2, 4, 4, 8, 13, 14, 26, 54, 43, 20, 64, 26, 63, 48, 118, 270, 151, 170, 55, 54, 229, 207, 274, 350, 323, 350, 376, 174, 433, 928, 494, 1054, 119, 440, 259, 664, 701, 208, 778, 328, 859, 516, 944, 504, 1033, 2160, 1126, 2350, 1223, 1274, 1324, 1376, 1429, 350
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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stn[n_]:=Module[{i=n+1, tn=(n(n+1)(n+2))/6}, While[!Divisible[(i(i+1) (i+2))/6, tn], i++]; i]; stn/@Range[70] (* Harvey P. Dale, Apr 11 2011 *)
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PROG
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(PARI) for(s=1, 80, n=s+1; while(frac(n*(n+1)*(n+2)/(s*(s+1)*(s+2)))>0, n++); print1(n, ", "); )
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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