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T(n, k) is the sum of the residues b^(p-1)-1 (mod p^2) for b=2..k, k > 1, where p = prime(n). Square array, read by downward antidiagonals, downward.
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array(rows, cols) = for(x=1, rows, for(y=2, cols, +1, print1(t(x, y), ", ")); print(""))
array(11, 12) \\ Print initial 11 rows and 12 columns of array
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AT(n, k) is the sum of the residues b^(p-1)-1 (mod p^2) for b=2..k, k > 1, where p = prime(n). Square array, read by antidiagonals, downward.
AT(n, k) = AT(n, k-1) if p is a base-k Wieferich prime.
A necessary condition for the failure of the first case of Fermat's last theorem for a prime p with prime index i is AT(i, k) = 0 for k = 2..113 (cf. Suzuki, 1994).
AT(n, 2) = A196202(n)-1.
(PARI) at(n, k) = my(p=prime(n)); sum(b=2, k, lift(Mod(b, p^2)^(p-1)-1))
array(rows, cols) = for(x=1, rows, for(y=2, cols, print1(at(x, y), ", ")); print(""))
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