Badulla Badu Numbers-------- -

A Badulla Badu Number is any integer that appears in the decimal expansion of ( \pi ) immediately after the digit ‘9’ and before a prime number, when read backward in base 7.

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Badulla Badu numbers form a curious, narrowly defined class of self-referential integers. They are distinct from Armstrong numbers and Dudeney numbers, though overlapping in isolated cases. In base 10, only (aside from trivial 1-digit numbers) satisfy the property. The concept serves as an interesting exercise in digit manipulation, exponential growth, and base representation, illustrating how tightly constrained such self-referential definitions can be. Badulla Badu Numbers--------

: Users are often asked to send money (via mobile reload or bank transfer) in advance for services that never materialize. A Badulla Badu Number is any integer that

Numbers satisfying all three are extraordinarily rare. As of this writing, only four are known: In base 10, only (aside from trivial 1-digit