A257560 First differences of A257559.

2, 3, 5, 7, 12, 13, 16, 20, 24, 27, 28, 33, 41, 43, 45, 48, 51, 56, 57, 62, 65, 69, 71, 76, 77, 82, 84, 86, 87, 88, 91, 92, 93, 96, 97, 103, 105, 106, 114, 116, 118, 125, 133, 135, 137, 140, 143, 147, 149, 155, 158, 162, 165, 167, 172, 176, 177, 183

Offset

1,1

Comments

By definition this sequence is strictly increasing. Heuristically a(n) is around 2n log n/log log n. - Charles R Greathouse IV, May 01 2015

Links

Zak Seidov, Table of n, a(n) for n = 1..1000

Formula

a(n) = A257559(n+1) - A257559(n).

Prog

(PARI) issemi(n)=bigomega(n)==2
t=0; v=List(); last=4; while(1, n=last+t; while(!issemi(n++), ); listput(v, t=n-last); if(v==100, return(Set(v))); last=n) \\ Charles R Greathouse IV, May 01 2015

Crossrefs

Cf. A257559.

Sequence in context: A260181 A140971 A073689 * A187774 A031216 A004683

Adjacent sequences: A257557 A257558 A257559 * A257561 A257562 A257563

Keyword

nonn

Author

Zak Seidov, Apr 30 2015

Status

approved