A110737 Row sums in A112668.

1, 4, 21, 40, 1555, 3906, 299593, 3280, 87381, 435848050, 67546215517, 61035156, 61054982558011, 328114698808274, 76861433640456465, 21523360, 128583032925805678351, 953674316406, 275941052631578947368421, 1743392200

Offset

1,2

Comments

For all n, a(n) is a term in row n of triangle A125118, and furthermore if n is prime then a(n) = A060072(n+1). - Mathew Englander, Dec 20 2020

Links

Michael De Vlieger, Table of n, a(n) for n = 1..388

Maple

A110737 := proc(n) local i, a ; if n = 1 then RETURN(1) ; else a := 2 ; while (1-a^n)/(1-a) mod n <> 0 do a := a+1 ; od ; RETURN( (1-a^n)/(1-a) ) ; fi ; end: for n from 1 to 25 do printf("%d, ", A110737(n)) : od : # R. J. Mathar, Mar 13 2007

Mathematica

Block[{a = {1}, k, s}, Do[k = 2; While[Mod[Set[s, Total@ NestList[# k &, 1, i - 1]], i] != 0, k++]; AppendTo[a, s], {i, 2, 20}]; a] (* Michael De Vlieger, Dec 31 2020 *)

Crossrefs

Cf. A110738, A110739, A125118, A060072.

Sequence in context: A086474 A085703 A063122 * A273417 A273443 A304467

Adjacent sequences: A110734 A110735 A110736 * A110738 A110739 A110740

Keyword

easy,nonn

Author

Amarnath Murthy, Aug 10 2005

Extensions

More terms from R. J. Mathar, Mar 13 2007

Status

approved