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!)
 A320537 Square array read by antidiagonals in which T(n,k) is the n-th even number j with the property that the symmetric representation of sigma(j) has k parts. 1
 2, 4, 10, 6, 14, 50, 8, 22, 70, 230, 12, 26, 98, 250, 1150, 16, 34, 110, 290, 1250 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This is a permutation of the positive even numbers (A299174). The union of all odd-indexed columns gives A319796, the even numbers in A071562. The union of all even-indexed columns gives A319802, the even numbers in A071561. a(21) > 5000. LINKS EXAMPLE The corner of the square array begins:    2, 10,  50, 230, 1150, ...    4, 14,  70, 250, 1250, ...    6, 22,  98, 290, ...    8, 26, 110, ...   12, 34, ...   16, ...   ... CROSSREFS Row 1 is A320521. Column 1 gives A174973 = A238443, without the 1. Column 2 gives A244894. Cf. A000203, A071561, A071562, A236104, A237593, A238443, A239663, A239665, A239929, A240062, A245092, A262626, A299174, A319796, A319802. Sequence in context: A098556 A159585 A130334 * A331708 A227289 A200742 Adjacent sequences:  A320534 A320535 A320536 * A320538 A320539 A320540 KEYWORD nonn,tabl,more,hard AUTHOR Omar E. Pol, Oct 15 2018 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 September 26 19:57 EDT 2021. Contains 347672 sequences. (Running on oeis4.)