A075569 a(1)=1, then smallest number >= the previous term such that every partial sum is a prime.

1, 1, 1, 2, 2, 4, 6, 6, 6, 8, 10, 12, 12, 12, 14, 16, 18, 18, 18, 24, 32, 34, 36, 38, 42, 46, 48, 54, 56, 64, 68, 78, 90, 90, 94, 102, 114, 122, 124, 134, 144, 148, 150, 152, 160, 168, 170, 178, 182, 190, 192, 200, 216, 220, 222, 234, 234, 234, 246, 260, 264, 268, 270

Offset

1,4

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

R:= 1: r:= 1: s:= 1:
for i from 2 to 100 do
    sp:= s;
    s:= nextprime(r+s-1);
    r:= s - sp;
    R:= R, r
od:
R; # Robert Israel, Jun 06 2025

Mathematica

a[1] = 1; a[n_] := a[n] = For[an = a[n-1], True, an++, If[AllTrue[ac = Rest @ Accumulate[Append[Array[a, n-1], an]], PrimeQ], Return[an]]]; Array[a, 100] (* Jean-François Alcover, Feb 17 2018 *)

Crossrefs

Sequence in context: A316788 A038759 A045999 * A338276 A062722 A160731

Adjacent sequences: A075566 A075567 A075568 * A075570 A075571 A075572

Keyword

nonn

Author

Amarnath Murthy, Sep 25 2002

Extensions

More terms from David Wasserman, Jan 20 2005

Status

approved