Aritmética
de salud cerebral 1
11.11=121 (121+23=144), 12.12=144 (144+25=169), 13.13=169
(169+27=196), 14.14=196 (196+29=225), 15.15=225 (225+31=256), 16.16=256 (256+33=289),
17.17=289 (289+35=324), 18.18=324 (324+37=361), 19.19=361 12+12=24-1=23, 13+13-1=25, 14+14-1=27,
15+15-1=29, 16+16-1=31, 17+17-1=33, 18+18-1=35, 19+19-1=37
Adelfo Morillo
Editado por María Ríos
