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A020643 a(n)-th squarefree is sum of first k squarefrees for some k. 0
1, 3, 5, 8, 12, 22, 36, 55, 77, 102, 133, 169, 187, 248, 296, 320, 343, 395, 483, 547, 652, 768, 809, 851, 893, 935, 1023, 1065, 1158, 1206, 1256, 1359, 1412, 1522, 1631, 1746, 1805, 1932, 1992, 2057, 2316, 2385, 2454, 2665, 2812, 2887, 3043, 3119, 3199, 3279 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..50.

CROSSREFS

Cf. A013930, A013931, A013932.

Sequence in context: A147879 A147880 A276527 * A131354 A092360 A129141

Adjacent sequences:  A020640 A020641 A020642 * A020644 A020645 A020646

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Renaud Lifchitz (100637.64(AT)CompuServe.COM), David W. Wilson

STATUS

approved

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Last modified February 20 06:26 EST 2019. Contains 320332 sequences. (Running on oeis4.)