A217971 a(n) = 2^(2*n+1) * (2*n+1)*n^(2*n).

24, 2560, 653184, 301989888, 220000000000, 231818611654656, 333360204766740480, 627189298506124754944, 1495163506861268427866112, 4404019200000000000000000000, 15705682358754099640245749284864, 66686788842514206222454073642188800, 332430457331186494783020411573611003904

Offset

1,1

Comments

Let S_(2*n+1)(m) denote difference between multiples of 2*n+1 in interval [0,m), m>=1, with even and odd digit sums in base 2*n. As is shown in the Shevelev and Moses link, a recursion for S_(2*n+1)(m) is connected with the periodicity of a special digit function, the smallest period of which is a(n).

Links

Andrew Howroyd, Table of n, a(n) for n = 1..100

Vladimir Shevelev and Peter J. C. Moses, A family of digit functions with large periods, arXiv:1209.5705 [math.NT], 2012.

Mathematica

Table[2^(2*n + 1)*(2*n + 1)*n^(2*n), {n, 15}] (* Wesley Ivan Hurt, Apr 28 2020 *)

Prog

(Maxima) A217971(n):=2^(2*n+1)*(2*n+1)*n^(2*n)$ makelist(A217971(n), n, 1, 10); /* Martin Ettl, Nov 15 2012 */
(PARI) a(n) = {2^(2*n+1) * (2*n+1)*n^(2*n)} \\ Andrew Howroyd, Apr 28 2020

Crossrefs

Cf. A214458, A218085.

Sequence in context: A008977 A159392 A064596 * A296652 A092706 A209708

Adjacent sequences: A217968 A217969 A217970 * A217972 A217973 A217974

Keyword

nonn

Author

Vladimir Shevelev and Peter J. C. Moses, Oct 16 2012

Extensions

Terms a(11) and beyond from Andrew Howroyd, Apr 28 2020

Status

approved