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A062948 H(A002808(n)) where H(n) is the half-totient function, H(n)=phi(n)/2:(A023022) and A002808(n) are the composites. 1
1, 1, 2, 3, 2, 2, 3, 4, 4, 3, 4, 6, 5, 4, 10, 6, 9, 6, 4, 8, 10, 8, 12, 6, 9, 12, 8, 6, 10, 12, 11, 8, 21, 10, 16, 12, 9, 20, 12, 18, 14, 8, 15, 18, 16, 24, 10, 16, 22, 12, 12, 18, 20, 18, 30, 12, 16, 27, 20, 12, 32, 21, 28, 20, 12, 36, 22, 30, 23, 36, 16, 21, 30, 20, 16, 24, 24, 26 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Harry J. Smith, Table of n, a(n) for n=1,...,1000

PROG

(PARI) H(n)=eulerphi(n)/2; j=[]; for(n=2, 200, if(isprime(n), n+1, j=concat(j, H(n) ))); j

(PARI) { n=0; for (m=2, 10^9, if (!isprime(m), write("b062948.txt", n++, " ", eulerphi(m)/2); if (n==1000, break)) ) } [From Harry J. Smith, Aug 14 2009]

CROSSREFS

Cf. A023022, A002808.

Sequence in context: A104377 A109337 A137266 * A096258 A049879 A053812

Adjacent sequences:  A062945 A062946 A062947 * A062949 A062950 A062951

KEYWORD

easy,nonn

AUTHOR

Jason Earls (zevi_35711(AT)yahoo.com), Jul 21 2001

EXTENSIONS

OFFSET changed from 2,3 to 1,3 by Harry J. Smith, Aug 14 2009

STATUS

approved

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Last modified December 7 23:55 EST 2016. Contains 278902 sequences.