a(n) is the smallest nonnegative integer such that a(n)! contains a string of exactly n consecutive 7's.

A254502

a(n) is the smallest nonnegative integer such that a(n)! contains a string of exactly n consecutive 7's.

Terms

    a(0) =0a(1) =6a(2) =31a(3) =48a(4) =22a(5) =599a(6) =1102a(7) =5280a(8) =4667a(9) =1753a(10) =48861a(11) =150336a(12) =223254a(13) =644487a(14) =7016773a(15) =9588848

External references