login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A110539 Diagonal sums of A110537 viewed as a number triangle. 2
1, 1, 2, 3, 4, 5, 8, 10, 15, 23, 35, 58, 101, 193, 381, 817, 1820, 4298, 10550, 27037, 71715, 197062, 558923, 1635948, 4932931, 15313467, 48883315, 160311731, 539527417, 1861545528, 6578404569, 23788920636, 87961893345, 332339327570 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..750

FORMULA

a(n) = Sum_{k=1..floor((n+1)/2)} Sum_{j=1..min(n-2k+2, k)} ceiling(j^(n-2k+2)/(n-2k+2)^j)*ceiling(j^k/k^j).

MATHEMATICA

A110539[n_] := Sum[Sum[ Ceiling[j^(n - 2*k + 2)/(n - 2*k + 2)^j] *Ceiling[j^k/k^j], {j, 1, Min[n - k + 1, k]}], {k, 1, Floor[n/2]}];

Table[A110539[n], {n, 1, 50}] (* G. C. Greubel, Aug 31 2017 *)

PROG

(PARI) for(n=1, 25, print1(sum(k=1, floor((n+1)/2), sum(j=1, min(n-2k+2, k), ceil(j^(n-2k+2)/(n-2k+2)^j)*ceil(j^k/k^j))), ", ")) \\ G. C. Greubel, Aug 31 2017

CROSSREFS

Sequence in context: A035555 A039875 A206555 * A222297 A211981 A019997

Adjacent sequences:  A110536 A110537 A110538 * A110540 A110541 A110542

KEYWORD

easy,nonn

AUTHOR

Paul Barry, Jul 25 2005

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 24 19:11 EDT 2020. Contains 338009 sequences. (Running on oeis4.)