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Adjusted joint rank sequence of (f(i)) and (g(j)) with f(i) before g(j) when f(i)=g(j), where f and g are the pentagonal numbers and the hexagonal numbers. Complement of A186328.
4

%I #13 Apr 16 2023 10:41:47

%S 2,4,6,8,10,12,14,17,19,21,23,25,27,30,32,34,36,38,40,42,45,47,49,51,

%T 53,55,58,60,62,64,66,68,70,73,75,77,79,81,83,86,88,90,92,94,96,98,

%U 101,103,105,107,109,111,114,116,118,120,122,124,127,129,131,133,135,137,139,142,144,146,148

%N Adjusted joint rank sequence of (f(i)) and (g(j)) with f(i) before g(j) when f(i)=g(j), where f and g are the pentagonal numbers and the hexagonal numbers. Complement of A186328.

%e First, write

%e 1..5...12....22.....35...... (pentagonal)

%e 1....6....15....28.......45.. (hexagonal)

%e Then replace each number by its rank, where ties are settled by ranking the pentagonal number before the hexagonal:

%e a=(1,3,5,7,9,11,13,15,16,....)=A186328

%e b=(2,4,6,8,10,12,14,17,19,...)=A186329.

%t (See A186328.)

%Y Cf. A186328, A186330, A186331.

%K nonn

%O 1,1

%A _Clark Kimberling_, Feb 17 2011

%E Terms corrected by _Clark Kimberling_ and _R. J. Mathar_, Jun 07 2011