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A331800
a(1) = 1; thereafter a(n) is the smallest number > a(n-1) which is neither of the form 2*a(i) nor Sum_{j=1..n-1} ( b_j*a(j) ) where 0 < i < n, b_j = 0 or 1.
1
1, 3, 5, 7, 17, 19, 50, 64, 152, 190, 470, 598, 1448, 1828, 4472, 5668, 13796, 17452, 42584, 53920, 131408, 166312, 405560, 513400, 1251584, 1584208, 3862592, 4889392, 11920400, 15088816, 36788000, 46566784, 113532416, 143710048, 350376032, 443509600, 1081305728
OFFSET
1,2
COMMENTS
Inserting the additional term a(0) = 2 would result in a so-called complete sequence after sorting. (The sorted sequence will then meet Brown's criterion.)
LINKS
Eric Weisstein's World of Mathematics, Brown's Criterion
Eric Weisstein's World of Mathematics, Complete Sequence
PROG
(PARI) /* a(n) for n>0 */
upto(lim)={my(a=[1], b=[]); for(i=1, lim, forsubset(#a, x, b=concat(b, [vecsum(vecextract(a, x))])); b=setminus(vecsort(b, , 8), a); for(j=1, #a, b=concat(b, [2*a[j]]); b=vecsort(b, , 8)); if(setsearch(b, i)==0, a=concat(a, [i]); a=vecsort(a, , 8)) ); a}
{ upto(200) }
CROSSREFS
Sequence in context: A248370 A087126 A348438 * A062547 A125739 A219461
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(13)-a(14) from Hugo Pfoertner, Jan 27 2020
More terms, using Rémy Sigrist's C++ at A331811 from Hugo Pfoertner, Jan 28 2020
STATUS
approved