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A131070
Number of pairs of integers (a, b) such that n=a+b and n=Sum_digits(a)^Sum_digits(b), n belonging to A131069.
1
1, 1, 3, 3, 1, 6, 5, 6, 6, 10, 3, 19, 20, 10, 6, 1, 1
OFFSET
0,3
EXAMPLE
For 2744 we have 19 pairs:
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.
CROSSREFS
Cf. A131069.
Sequence in context: A065227 A208539 A174128 * A295290 A165202 A010468
KEYWORD
hard,nonn
AUTHOR
Paolo P. Lava, Jun 13 2007, Jun 15 2007
STATUS
approved