A101947 A101909 sorted and duplicates removed.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73

Offset

1,2

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Prog

(PARI) bet2n4n(n) = { local(c, c1, x, y); a=vector(5001); for(x=1, n, c=0; forprime(y=2*x+1, 4*x-1, c++; ); a[x] = c; ); b=vecsort(a); for(x=1, 5000, if(b[x]>0, if(b[x]<>b[x+1], print1(b[x]", ") ) ); ) }
(PARI) s=0; v=vectorsmall(10^6, n, s+=isprime(4*n-1)+isprime(4*n-3)-isprime(2*n-1)); v=vecsort(v, , 8); vecextract(v, Str("1..", #v\2)) \\ Charles R Greathouse IV, Mar 12 2012

Crossrefs

Cf. A101909, A101983-A101985.

Sequence in context: A353888 A331162 A337843 * A183223 A167520 A051882

Adjacent sequences: A101944 A101945 A101946 * A101948 A101949 A101950

Keyword

easy,nonn

Author

Cino Hilliard, Jan 28 2005

Status

approved