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A087474 Triangle T(n,k), read by rows, in which the n-th row gives the n successive iterations of f(m) on A087473(n), where f(m) is product of the two numbers formed from the alternating digits of m.

%I A087474 #8 Mar 14 2015 09:42:39
%S A087474 1,10,0,25,10,0,39,27,14,4,77,49,36,18,8,171,77,49,36,18,8,199,171,77,
%T A087474 49,36,18,8,577,399,351,155,75,35,15,5,887,696,594,486,368,228,56,30,
%U A087474 0,1592,988,784,592,468,288,224,48,32,6,2682,1736,988,784,592,468,288,224
%N A087474 Triangle T(n,k), read by rows, in which the n-th row gives the n successive iterations of f(m) on A087473(n), where f(m) is product of the two numbers formed from the alternating digits of m.
%F A087474 T(0, 0)=1, T(n, 0)=A087473(n), T(n, k+1) = f(T(n, k)), where f(m) is the product of the two numbers formed by the alternating digits of m.
%e A087474 The 4th row is {77,49,36,18,8} since f(77)=49, f(49)=36, f(36)=18, f(18)=8.
%e A087474 {1},
%e A087474 {10,0},
%e A087474 {25,10,0},
%e A087474 {39,27,14,4},
%e A087474 {77,49,36,18,8},
%e A087474 {171,77,49,36,18,8},
%e A087474 {199,171,77,49,36,18,8},
%e A087474 {577,399,351,155,75,35,15,5},...
%Y A087474 Cf. A087471, A087472, A087473.
%K A087474 nonn,tabl,base
%O A087474 0,2
%A A087474 _Amarnath Murthy_ and _Paul D. Hanna_, Sep 11 2003