a(n) is the numerator of Sum_{k=0..n} 1 / (k!)^2.

A354302

a(n) is the numerator of Sum_{k=0..n} 1 / (k!)^2.

Terms

    a(0) =1a(1) =2a(2) =9a(3) =41a(4) =1313a(5) =5471a(6) =1181737a(7) =28952557a(8) =1235309099a(9) =150090055529

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