The tetrahedral numbers

HTTP/1.1 500 Internal Server Error Date: Mon, 16 Mar 2026 03:24:00 GMT Server: CL-HTTP/70.217 (LispWorks; 2.1.7) Connection: close Content-Type: text/html; charset=ISO-8859-1 Transfer-Encoding: chunked Internal Server Error

Internal Server Error

No applicable methods for #<STANDARD-GENERIC-FUNCTION NUMBERS::APPLY-FN 22A76A22> with args (1 0 NIL 1 :QUADRATIC (0 -1/6 1/6))

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