OFFSET
1,1
COMMENTS
Compactification of row n of A237591 via product of prime powers. Row n of A237591 is interpreted instead as row n of A067255, returning index n from that sequence.
All terms are even.
Subset of A055932, but not a subset of A025487, since row n = 14 of A237591 is {8,3,1,2}. It is the least n such that at least one pair of terms in the row exhibit increase.
Intersection with A002182 = {2, 4, 12, 24, 240, 720, 20160} and is finite on account of the prime shape of a(n).
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..1594
Michael De Vlieger, Log-log scatterplot of a(n) for n=1..2^16.
EXAMPLE
MATHEMATICA
Table[Times @@ Flatten@ MapIndexed[Prime[#2]^#1 &, #] &@ Array[(Ceiling[(n + 1)/# - (# + 1)/2] - Ceiling[(n + 1)/(# + 1) - (# + 2)/2]) &, Floor[(Sqrt[8 n + 1] - 1)/2]], {n, 28}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Michael De Vlieger, Oct 29 2021
STATUS
approved