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A097557 a(n+1) = a(n) + number of nonprimes so far; a(1) = 1. 0
1, 2, 3, 4, 6, 9, 13, 17, 21, 26, 32, 39, 47, 55, 64, 74, 85, 97, 109, 121, 134, 148, 163, 178, 194, 211, 228, 246, 265, 285, 306, 328, 351, 375, 400, 426, 453, 481, 510, 540, 571, 602, 634, 667, 701, 735, 770, 806, 843, 881, 919, 957, 996, 1036, 1077, 1119 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

EXAMPLE

a(2) = a(1) + #{1} = 1 + 1 = 2;

a(3) = a(2) + #{1} = 2 + 1 = 3;

a(4) = a(3) + #{1} = 3 + 1 = 4;

a(5) = a(4) + #{1,4} = 4 + 2 = 6;

a(6) = a(5) + #{1,4,6} = 6 + 3 = 9;

a(7) = a(6) + #{1,4,6,9} = 9 + 4 = 13;

a(8) = a(7) + #{1,4,6,9} = 13 + 4 = 17;

a(9) = a(8) + #{1,4,6,9} = 17 + 4 = 21;

a(10) = a(9) + #{1,4,6,9,21} = 21 + 5 = 26.

CROSSREFS

Sequence in context: A056751 A189035 A137446 * A175848 A123648 A129632

Adjacent sequences:  A097554 A097555 A097556 * A097558 A097559 A097560

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Aug 27 2004

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Last modified February 16 17:11 EST 2012. Contains 205938 sequences.