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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 (list; graph; refs; listen; history; text; internal format)
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

Peter J. C. Moses, Table of n, a(n) for n = 1..1000

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

Cf. A248138, A248140, A248145, A248146, A248171, A248172.

Sequence in context: A212608 A212611 A004005 * A143404 A051028 A076011

Adjacent sequences:  A248006 A248007 A248008 * A248010 A248011 A248012

KEYWORD

nonn,base

AUTHOR

Vladimir Shevelev, Oct 05 2014

EXTENSIONS

More terms from Peter J. C. Moses, Oct 09 2014

STATUS

approved

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Last modified January 20 10:32 EST 2022. Contains 350472 sequences. (Running on oeis4.)