A136311 - OEIS

%I #9 Sep 21 2015 01:35:11

%S 1,1,2,1,2,3,1,2,3,6,1,2,3,4,12,1,2,3,4,8,22,1,2,3,4,5,12,43,1,2,3,4,

%T 5,10,21,79,1,2,3,4,5,6,15,37,157,1,2,3,4,5,6,12,27,73,310,1,2,3,4,5,

%U 6,7,18,49,137,610,1,2,3,4,5,6,7,14,33,84,258,1205,1,2,3,4,5,6,7,8,21,61

%N Array read by antidiagonals: a(1) = 1; a(n+1) = a(n) + (largest k-gonal number <= a(n)).

%e The array begins:

%e ==================================================================

%e n=..|.1.|.2.|.3.|.4.|..5.|..6.|..7.|..8.|...9.|..10.|..11.|...12.|

%e ==================================================================

%e k=3.|.1.|.2.|.3.|.6.|.12.|.22.|.43.|.79.|.157.|.310.|.610.|.1205.|.A060985

%e k=4.|.1.|.2.|.3.|.4.|..8.|.12.|.21.|.37.|..73.|.137.|.258.|..514.|.A060984

%e k=5.|.1.|.2.|.3.|.4.|..5.|.10.|.15.|.27.|..49.|..84.|.154.|..299.|

%e k=6.|.1.|.2.|.3.|.4.|..5.|..6.|.12.|.18.|..33.|..61.|.106.|..197.|

%e k=7.|.1.|.2.|.3.|.4.|..5.|..6.|..7.|.14.|..21.|..39.|..73.|..128.|

%e k=8.|.1.|.2.|.3.|.4.|..5.|..6.|..7.|..8.|..16.|..24.|..45.|...85.|

%e k=9.|.1.|.2.|.3.|.4.|..5.|..6.|..7.|..8.|...9.|..18.|..27.|...51.|

%e ==================================================================

%p A081422 := proc(k,n) n/2*((k-2)*n-k+4) ; end: A136311 := proc(k,n) option remember ; local aprev,n2 ; if n = 1 then RETURN(1) ; else aprev := A136311(k,n-1) ; for n2 from 0 do if A081422(k,n2) > aprev then RETURN( aprev+A081422(k,n2-1)); fi; od: fi ; end: for d from 4 to 20 do for n from 1 to d-3 do printf("%d,", A136311(d-n,n)) ; od: od: # _R. J. Mathar_, Jun 12 2008

%Y Cf. A060984, A060985.

%K easy,nonn,tabl

%O 1,3

%A _Jonathan Vos Post_, Mar 22 2008

%E More terms from _R. J. Mathar_, Jun 12 2008