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A088079
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Diagonal T(n,n) of the triangle T(n,k), n>=0, 0<=k<=n, in which row n contains n+1 consecutive integers T(n,k+1)=T(n,k)+1 such that T(n,k) is divisible by a k-th power.
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1
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OFFSET
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0,2
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LINKS
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EXAMPLE
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In row n=4, T(4,4)=352 is divisible by 2^4, T(4,3)=351 is divisible by 3^3, T(4,2)= 350 is divisible by 5^2 and T(4,1)=349 is divisible by 349^1 and T(4,0) is divisible by any x^0.
Table starts
1;
1,2;
2,3,4;
61,62,63,64;
348,349,350,351,352;
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PROG
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(PARI)
okdivs(n, k) = {fordiv(n, d, if (d != 1 && ispower(d, k), return (1))); return (0); }
oknbrs(n, i) = {my(k); forstep (k=n, 2, -1, if (! okdivs(i+k, k), return (0)); ); return (i); }
row(n) = {if (n == 0, print(1); return; ); my(i = 1); while (1, if (oknbrs(n, i), for (k=0, n, print1(i+k, ", ")); print(); return; ); i++; ); }
tabl(nn) = {for (n=0, nn, row(n); ); }
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CROSSREFS
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KEYWORD
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more,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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