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*ettore majorana (1906–1938) could multiply two 3 digit numbers in his head in seconds at the age of 4.
*ettore majorana (1906–1938) could multiply two 3 digit numbers in his head in seconds at the age of 4.

conclusiones: sabíamos que el valor de la suma de todos los números de la parte “interior” era 53 (ver mi tópico sobre el tema en el foro en inglés “why in a 4x4 numbers in corners are those in inner area (1)”, es decir, “¿por qué en un 4x4 los números en las esquinas deben ser los mismos que en el área interior?”), igual a la adición de las cuatro esquinas más “2 líneas” en este crucigrama 6x6, o sea, 2 + 5 + 3 + 1 + 2 x 21 = 11 + 42, o, simplemente, en este caso, el total del crucigrama menos el borde, 6 x 21 - 2 - 14 - 5 - 15 - 1 - 17 - 3 - 16 = 126 - 73 = 53.
conclusions: we knew that the total addition value of the inner part was 53 (see my topic on this subject, “why in a 4x4 numbers in corners are those in inner area (1)”), the addition of the four corners plus 2 lines in this puzzle, that is, 2 + 5 + 3 + 1 + 2 x 21 = 11 + 42, or simply in this case the total puzzle minus the border, 6 x 21 - 2 - 14 - 5 - 15 - 1 - 17 - 3 - 16 = 126 - 73 = 53. in these conditions, once the cages “96x”, “7+” and “0-“ have been defined in the inner area, the sum of cages “30x” and “1-“ equals 13 (53 - 14 - 7 - 12 - 7) so (see my topic “the use of maximums and minimums in the sum of cages”) since the minimum value of “1-“ is 3 (1-2) the maximum value of “30x” would be 10 and the combination 5-1-6 impossible.