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A182719
Numbers of the form 5k + 4, 7k + 5, or 11k + 6.
3
4, 5, 6, 9, 12, 14, 17, 19, 24, 26, 28, 29, 33, 34, 39, 40, 44, 47, 49, 50, 54, 59, 61, 64, 68, 69, 72, 74, 75, 79, 82, 83, 84, 89, 94, 96, 99, 103, 104, 105, 109, 110, 114, 116, 117, 119, 124, 127, 129, 131, 134, 138, 139, 144, 145, 149, 152, 154, 159, 160, 164
OFFSET
1,1
COMMENTS
Numbers such that the Ramanujan congruences apply, making p(a(n)) divisible by at least one of 5, 7, or 11, where p is A000041.
Union of A016897, A017041 and A017461.
First differences are periodic with period length 145.
FORMULA
a(n) = a(n-145) + 385 = a(n-1) + a(n-145) - a(n-146).
MATHEMATICA
Union[With[{no=30}, Join[5Range[0, no]+4, 7Range[0, no]+5, 11Range[0, no]+6]]] (* Harvey P. Dale, Feb 18 2011 *)
PROG
(Magma) IsA182719:=func< n | exists{ k: k in [0..n div 5] | n in [5*k+4, 7*k+5, 11*k+6] } >; [ n: n in [1..160] | IsA182719(n) ]; // Klaus Brockhaus, Feb 08 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Omar E. Pol, Feb 08 2011
EXTENSIONS
Rewritten by Charles R Greathouse IV and Klaus Brockhaus, Feb 08 2011
STATUS
approved