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A138856 Numbers such that all subsets of {prime(a(1)),...,prime(a(n))} have a different sum. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

see A138000,A138857,A138858.

LINKS

Table of n, a(n) for n=1..30.

FORMULA

A138856(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

Cf. A138000-138001, A138857-A138858, A064934.

Sequence in context: A059994 A299492 A253198 * A018401 A049332 A096570

Adjacent sequences:  A138853 A138854 A138855 * A138857 A138858 A138859

KEYWORD

nonn

AUTHOR

M. F. Hasler, Apr 10 2008

EXTENSIONS

a(22)-a(30) from Donovan Johnson, Oct 03 2009

STATUS

approved

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Last modified November 21 09:56 EST 2019. Contains 329362 sequences. (Running on oeis4.)