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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A359193 a(n) is the index of the smallest square pyramidal number with exactly n prime factors (counted with multiplicity).

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%I A359193 #11 Feb 16 2025 08:34:04
%S A359193 1,2,3,4,7,15,24,31,63,80,175,255,511,1023,512,6912,2047,6655,14336,
%T A359193 16384,32767,90112,131071,180224,483327,1114112,1638400,2097151,
%U A359193 1048575,16777216,8388607,33357824,16777215,92274687,67108864
%N A359193 a(n) is the index of the smallest square pyramidal number with exactly n prime factors (counted with multiplicity).
%H A359193 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PrimeFactor.html">Prime Factor</a>
%H A359193 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SquarePyramidalNumber.html">Square Pyramidal Number</a>
%o A359193 (PARI) sp(n) = n*(n+1)*(2*n+1)/6; \\ A000330
%o A359193 a(n) = my(k=1); while (bigomega(sp(k)) != n, k++); k; \\ _Michel Marcus_, Dec 20 2022
%Y A359193 Cf. A000330, A001222, A359192.
%K A359193 nonn,more
%O A359193 0,2
%A A359193 _Ilya Gutkovskiy_, Dec 19 2022
%E A359193 a(26)-a(34) from _Daniel Suteu_, Dec 29 2022