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A228433
Smallest starting abundant number for n consecutive abundant numbers in arithmetic progression.
8
24, 114, 114, 228, 1242, 221355126
OFFSET
3,1
COMMENTS
The next term is a(9) > 10^9. The common difference for first 7 terms is 6 and for 8th term is 2.
EXAMPLE
First and smallest occurrence of n, n >= 3, consecutive abundant numbers in arithmetic progression:
a(3) = 24: (24, 30, 36);
a(4) = 114: (114, 120, 126, 132);
a(5) = 114: (114, 120, 126, 132, 138);
a(6) = 228: (228, 234, 240, 246, 252, 258);
a(7) = 1242: (1242, 1248, 1254, 1260, 1266, 1272, 1278);
a(8) = 221355126: (221355126, 221355128, 221355130, 221355132, 221355134, 221355136, 221355138, 221355140);
CROSSREFS
Cf. A005101.
Sequence in context: A281133 A064595 A064591 * A124952 A126411 A211580
KEYWORD
nonn,hard,more
AUTHOR
Shyam Sunder Gupta, Nov 10 2013
STATUS
approved