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A370520 Triangular numbers (A000217) in A353729. 0
1, 3, 6, 55, 66, 666, 1128, 1326, 2346, 31626, 133386, 193131, 212226, 236328, 283128, 416328, 881128, 1211346, 1222266, 1466328, 1777555, 2263128, 11293128, 14191128, 16111326, 16316328, 22121226, 22261128, 26263128, 31621128, 32292666, 33321366, 33533955, 39139128 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Intersection of A000217 and A353729.
The sequence is infinite because the numbers T(1327) = 881128, T(13327) = 88811128, T(133327) = 8888111128, ..... are terms.
Also, the numbers T(651) = 21226, T(6651) = 22121226, T(66651) = 2221211226, T(666651) = 222212111226.... or T(672) = 226128, T(6672) = 22261128, T(66672) = 2222611128, ... are terms.
LINKS
EXAMPLE
2346 = A000217(68) and 346 = 2*173, 246 = 3*82, 234 = 6*39, so 2346 is a term.
PROG
(Magma) ints:=func<n| n eq 0 select[0] else Intseq(n)>; f:=func<n, i|Seqint([ints(n)[j]:j in [1..#ints(n)]|j ne (#ints(n)-i+1)])>; [p:p in [s*(s+1) div 2:s in [1..10000]]|not 0 in ints(p) and forall{i:i in [1..#ints(p)]|IsIntegral( f(p, i)/ ints(p)[(#Intseq(p)-i+1)] )}];
CROSSREFS
Sequence in context: A051641 A003098 A045914 * A303351 A067610 A067609
KEYWORD
nonn,base
AUTHOR
Marius A. Burtea, Feb 27 2024
STATUS
approved

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Last modified July 19 16:24 EDT 2024. Contains 374410 sequences. (Running on oeis4.)