A145915 Even composites in A145832.
146, 164, 458, 524, 584, 626, 764, 956, 1084, 1172, 1322, 1478, 1858, 1934, 2138, 2174, 2336, 2966, 3158, 3464, 3548, 3566, 3884, 3974, 3998, 4124, 4274, 4346, 4696, 5042, 5102, 5246, 5354, 5414, 6002, 6038, 6434, 6626, 6646, 6782, 6884, 7034, 7094
Offset: 1
Keywords
Examples
146 = 2*73 is even and composite, 1, 2, 73, 146 are its divisors. 1+146/1 = 146+146/146 = 147 = 3*7^2 and 7 < 12 < sqrt(147); 2+146/2 = 73+146/73 = 75 = 3*5^2 and 5 < 8 < sqrt(75). Hence 146 is in the sequence.
Links
- Eric Weisstein's World of Mathematics, Round Number
Programs
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Magma
[ n: n in [4..7100 by 2] | forall{ k: k in [ Integers()!(d+n/d): d in [ D[j]: j in [1..a] ] ] | k ge (IsEmpty(T) select 1 else Max(T) where T is [ x[1]: x in Factorization(k) ])^2 } where a is IsOdd(#D) select (#D+1)/2 else #D/2 where D is Divisors(n) ];
Comments