Is there a formula for the sum $s(n)=\sum_{k=1}^n2^{k^2}$? I know that $\sum^n2^k=2(2^n-1)$ but I dont know if I can use that. If not, is there a big-O upper bound?
2026-04-01 21:27:44.1775078864
Formula for $\sum2^{k^2}$
87 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in SUMMATION
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