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A378632
Numbers that set records in A378181.
1
1, 4, 6, 12, 24, 48, 60, 96, 120, 240, 420, 480, 840, 1680, 3360, 6720, 13440, 18480, 26880, 36960, 53760, 73920, 147840, 295680, 480480, 591360, 960960, 1182720, 1921920, 3843840, 7687680, 15375360, 30750720, 61501440, 65345280, 123002880, 130690560, 246005760
OFFSET
1,2
COMMENTS
Numbers n that set records for binomial(bigomega(n)+omega(n)-1, omega(n)), where bigomega = A001222 and omega = A001221.
a(n) is of the form 2^k * P(i), k >= 0, where primorial P = A002110.
Proper subset of A070175.
LINKS
MATHEMATICA
f[x_] := Block[{i, k, m, nn, p}, nn = Product[Prime[j], {j, x}]; Set[{k, i, p}, Range[0, 2]]; {1}~Join~Union@ Reap[Until[i > x, While[Set[m, 2^k*p] <= nn, Sow[m]; k++]; k = 0; i++; p *= Prime[i] ] ][[-1, 1]] ] (* generate A070175 *);
r = 0; Reap[Do[If[# > r, r = #; Sow[n]] &@ Binomial[#2 + #1 - 1, #1] & @@ {PrimeNu[n], PrimeOmega[n]}, {n, f[10]}] ][[-1, 1]]
KEYWORD
nonn,easy,new
AUTHOR
Michael De Vlieger, Dec 02 2024
STATUS
approved