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A069579 revision #3

A069579

phi(core(n))=core(phi(n)) where core(x) is the square-free part of x; the smallest integer such that x*core(x) is a square.

1, 2, 3, 6, 7, 8, 11, 14, 22, 23, 24, 27, 31, 32, 43, 46, 47, 54, 56, 59, 62, 67, 71, 79, 83, 86, 88, 94, 96, 103, 107, 118, 128, 131, 134, 139, 142, 158, 166, 167, 179, 184, 191, 206, 211, 214, 216, 223, 224, 227, 239, 243, 248, 262, 263, 278, 283, 311, 331, 334

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

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..60.

PROG

(PARI) for(n=1, 500, if(core(eulerphi(n))==eulerphi(core(n)), print1(n, ", ")))

CROSSREFS

Sequence in context: A155152 A098740 A116046 * A327176 A065193 A116047

Adjacent sequences: A069576 A069577 A069578 * A069580 A069581 A069582

KEYWORD

easy,nonn,new

AUTHOR

Benoit Cloitre (abmt(AT)wanadoo.fr), Apr 18 2002

STATUS

approved