a number is happy if the sum of the first three digits equals the sum of the last three digits.(adsbygoogle = window.adsbygoogle || []).push({});

how many 6 digit happy numbers are there?

a slightly easier but very similar question how mnay happy 6 number strings are there? (in case you dont see the difference, a number cannot start with 0, while a 6 digit "string" can.)

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# Happy numbers

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