Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #20 Dec 07 2019 12:18:29
%S 1,1,3,1,4,6,1,4,3,10,1,4,8,7,15,1,4,8,3,6,21,1,4,8,13,7,11,28,1,4,8,
%T 13,3,12,10,36,1,4,8,13,19,7,6,16,45,1,4,8,13,19,3,12,11,15,55,1,4,8,
%U 13,19,26,7,18,17,22,66,1,4,8,13,19,26,3,12,6,10,21,78,1,4,8,13,19,26,34,7,18,11,16,29,91,1,4,8,13,19,26,34,3,12,25,17,23,28,105
%N Lower triangular region of array A286156, transposed.
%H Antti Karttunen, <a href="/A286159/b286159.txt">Table of n, a(n) for n = 1..10585; the first 145 rows of the triangle</a>
%e The first ten rows of this triangular array:
%e 1,
%e 1, 3,
%e 1, 4, 6,
%e 1, 4, 3, 10,
%e 1, 4, 8, 7, 15,
%e 1, 4, 8, 3, 6, 21,
%e 1, 4, 8, 13, 7, 11, 28,
%e 1, 4, 8, 13, 3, 12, 10, 36,
%e 1, 4, 8, 13, 19, 7, 6, 16, 45,
%e 1, 4, 8, 13, 19, 3, 12, 11, 15, 55
%t Map[((#1 + #2)^2 + 3 #1 + #2)/2 & @@ # & /@ Reverse@ # &, Table[Reverse@ QuotientRemainder[n, k], {n, 14}, {k, n}]] // Flatten (* _Michael De Vlieger_, May 20 2017 *)
%o (Scheme) (define (A286159 n) (A286156bi (A002024 n) (A004736 n))) ;; For A286156bi see A286156.
%o (Python)
%o def T(a, b): return ((a + b)**2 + 3*a + b)/2
%o def a(n, k): return T(n%k, int(n/k))
%o for n in range(1, 21): print [a(n , k) for k in range(1, n + 1)][::-1] # _Indranil Ghosh_, May 20 2017
%Y Transpose: A268158.
%Y Cf. A000012, A000217, A268156, A268157.
%Y Rows converge towards A034856.
%K nonn,tabl
%O 1,3
%A _Antti Karttunen_, May 04 2017