A062948 a(n) = 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, 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

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)) ) } \\ Harry J. Smith, Aug 14 2009

Crossrefs

Cf. A023022, A002808.

Sequence in context: A303539 A303540 A137266 * A365159 A358639 A358640

Adjacent sequences: A062945 A062946 A062947 * A062949 A062950 A062951

Keyword

easy,nonn

Author

Jason Earls, Jul 21 2001

Extensions

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

Status

approved