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A248009
Partition of the positive odd integers into minimal blocks such that the concatenation of the numbers in each block is an evil number (A001969). Sequence lists the evil numbers obtained in this way.
4
135, 7911, 131517, 19212325272931, 33, 35373941, 43, 45, 4749, 51, 53, 5557, 596163, 65, 676971, 737577, 798183, 85, 8789, 9193, 95, 9799101103105, 107109, 111, 113, 115117119, 121123125127129, 131133, 135, 137139, 141, 143145147, 149, 151153155157, 159
OFFSET
1,1
COMMENTS
The numbers of the consecutive positive odd integers in the blocks of the partition are 3,3,3,7,1,4,1,1,2,1,1,2,3,1,3,3,3,1,2,2,...
LINKS
EXAMPLE
a(1)=135, since 1 and 13 are odious numbers, while 135 is evil.
PROG
(PARI) lista(nn) = {s = ""; forstep(n=1, nn, 2, ns = concat(s, Str(n)); if ((hammingweight(eval(ns)) % 2) == 0, print1(ns, ", "); s = "", s = ns); ); } \\ Michel Marcus, Oct 09 2014
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Vladimir Shevelev, Oct 05 2014
EXTENSIONS
More terms from Peter J. C. Moses, Oct 09 2014
STATUS
approved