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A049201 If n is not composite, a(n) = n followed by 1; if n is composite, a(n) = concatenation of prime factors of n. 1
1, 11, 21, 31, 22, 51, 23, 71, 222, 33, 25, 111, 223, 131, 27, 35, 2222, 171, 233, 191, 225, 37, 31, 231, 2223, 55, 33, 333, 227, 291, 235, 311, 22222, 41, 37, 57, 2233, 371, 39, 43, 2225, 411, 237, 431, 231, 335, 43, 471, 22223, 77, 255, 47, 233, 531, 2333, 61 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..55.

CROSSREFS

Cf. A049121, A037274.

Sequence in context: A109686 A077522 A308232 * A068633 A225297 A123849

Adjacent sequences:  A049198 A049199 A049200 * A049202 A049203 A049204

KEYWORD

nonn,base,easy

AUTHOR

N. J. A. Sloane

EXTENSIONS

More terms from Michel ten Voorde

STATUS

approved

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Last modified April 16 18:53 EDT 2021. Contains 343050 sequences. (Running on oeis4.)