%I #7 Feb 02 2013 13:51:24

%S 1,1,3,3,1,6,5,6,6,10,3,19,20,10,6,1,1

%N Number of pairs of integers (a, b) such that n=a+b and n=Sum_digits(a)^Sum_digits(b), n belonging to A131069.

%e For 2744 we have 19 pairs:

%e 2741,3; 2732,12; 2723,21; 2714,30; 2642,102; 2633,111; 2624,120; 2543,201; 2534,210; 2444,300; 2100,644; 2010,734; 2001,743; 1742,1002; 1733,1011; 1724,1020; 1643,1101; 1634,1110; 1544,1200.

%Y Cf. A131069.

%K hard,nonn

%O 0,3

%A _Paolo P. Lava_, Jun 13 2007, Jun 15 2007