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A078198
Numbers that cannot be partitioned into distinct powers of 3, 5 and 7, all with positive exponents.
0
1, 2, 4, 6, 11, 13, 18, 20, 22, 23, 26, 29, 31, 38, 45, 47, 50, 53, 72, 75, 78, 80, 87, 94, 99, 103, 107, 112, 119, 126, 131, 156, 175, 200, 205, 212, 219, 224, 228, 232, 237, 244, 256, 281, 293, 318, 330, 337, 342, 369, 374, 418, 455, 462, 499, 543, 548, 575
OFFSET
1,2
COMMENTS
Comment from Don Reble, Apr 05 2010: This appears to be a finite sequence. It's straightforward to show that a(377)=40876617, and that there are no more terms below 41583755582761723342524882185. After that, I'm stuck.
EXAMPLE
6 is here because 3+3 doesn't count (not all distinct); 5+1 doesn't count (zero exponent).
2271 is not a member because 2271 = 3^1+3^2+3^3+3^4+3^5+3^6 + 5^1+5^2+5^3+5^4 + 7^1+7^2+7^3
CROSSREFS
Cf. A174656.
Sequence in context: A224860 A327309 A350668 * A171865 A372622 A344622
KEYWORD
nonn
AUTHOR
Wouter Meeussen, Mar 20 2010
EXTENSIONS
Edited by Don Reble, Apr 05 2010
STATUS
approved