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A138850 Weird numbers (A006037) not divisible by 5. 2
836, 7192, 7912, 9272, 10792, 17272, 45356, 73616, 83312, 91388, 113072, 222952, 243892, 254012, 338572, 343876, 351956, 388076, 407132, 410476, 465652, 470668, 475684, 477356, 482372, 490732, 495748, 500764, 502436, 507452, 512468, 515812 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Up to 200000, there are only 11 weird numbers not divisible by 5.

Since no A006037(k) < 10^17 is odd, at least up to there, "divisible by 5" is equivalent to "ending in 0" (in base 10).

It appears that 4*11*19*p is an element of this sequence for p=1 and all primes p>547. Moreover, these seem to comprise most of the terms of this sequence.

Up to n=500, the only indices for which a(n) is not of this form are n=2,...,16, 18, 34, 38, 43, 64, 83, 148, 158, 236, 266, 296, 310.

LINKS

M. F. Hasler, Table of n, a(n) for n=1,...,500.

PROG

(PARI) t=0; A138850=vector(50, i, until( (t+=2)%5 && is_A006037(t), ); t) \\ [Updated by M. F. Hasler, Jan 07 2014]

CROSSREFS

Cf. A006037, A100696.

Sequence in context: A245947 A235288 A162945 * A016113 A177846 A167603

Adjacent sequences:  A138847 A138848 A138849 * A138851 A138852 A138853

KEYWORD

nonn

AUTHOR

M. F. Hasler, Apr 02 2008

STATUS

approved

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Last modified December 2 21:20 EST 2016. Contains 278694 sequences.