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A138856
Numbers such that all subsets of {prime(a(1)), ..., prime(a(n))} have a different sum.
1
1, 2, 4, 5, 10, 16, 28, 47, 83, 147, 267, 481, 882, 1621, 2997, 5578, 10428, 19560, 36849, 69649, 131983, 250841, 477992, 912662, 1746404, 3347928, 6429526, 12366247, 23820901, 45947255, 88742186, 171594310, 332169919, 643674781, 1248523100, 2423948034
OFFSET
1,2
COMMENTS
FORMULA
a(n) = primepi(A138000(n)).
PROG
(PARI) {s=1; p=0; for( n=1, 20, until( !bitand( s, s>>prime(p++) ), ); s+=s<<prime(p); print1( p, ", "))}
CROSSREFS
KEYWORD
nonn
AUTHOR
M. F. Hasler, Apr 10 2008
EXTENSIONS
a(22)-a(30) from Donovan Johnson, Oct 03 2009
a(31)-a(36) from Amiram Eldar, Sep 06 2024
STATUS
approved