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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A339496 T(n, k) = Sum(divisors(k) union {k*j : j = 2..floor(n/k)}). Triangle read by rows. 3
 1, 3, 3, 6, 3, 4, 10, 7, 4, 7, 15, 7, 4, 7, 6, 21, 13, 10, 7, 6, 12, 28, 13, 10, 7, 6, 12, 8, 36, 21, 10, 15, 6, 12, 8, 15, 45, 21, 19, 15, 6, 12, 8, 15, 13, 55, 31, 19, 15, 16, 12, 8, 15, 13, 18, 66, 31, 19, 15, 16, 12, 8, 15, 13, 18, 12, 78, 43, 31, 27, 16, 24, 8, 15, 13, 18, 12, 28 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS For the connection with paths in the divisor graph of {1,...,n} see the comment in A339492. LINKS EXAMPLE The triangle starts: [1]                       1; [2]                      3, 3; [3]                    6, 3, 4; [4]                  10, 7, 4, 7; [5]                15, 7, 4, 7, 6; [6]              21, 13, 10, 7, 6, 12; [7]            28, 13, 10, 7, 6, 12, 8; [8]          36, 21, 10, 15, 6, 12, 8, 15; [9]        45, 21, 19, 15, 6, 12, 8, 15, 13; [10]     55, 31, 19, 15, 16, 12, 8, 15, 13, 18. MAPLE t := (n, k) -> NumberTheory:-Divisors(k) union {seq(k*j, j=2..n/k)}: T := (n, k) -> add(j, j = t(n, k)): for n from 1 to 10 do seq(T(n, k), k=1..n) od; CROSSREFS T(n, 1) = A000217(n), T(n, n) = A000203(n), T(2n, n) = A224880(n). Cf. A339491, A339492, A339489. Sequence in context: A034188 A184849 A335870 * A336422 A040007 A110634 Adjacent sequences:  A339493 A339494 A339495 * A339497 A339498 A339499 KEYWORD nonn,tabl AUTHOR Peter Luschny, Dec 31 2020 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.

Last modified April 17 22:40 EDT 2021. Contains 343071 sequences. (Running on oeis4.)